The process of scientific method involves making hypotheses , driving predictions from them as logical consequences , and then carrying out experiments or empirical observations based on those predictions. A hypotheses is a conjecture , based on knowledge obtained while seeking answers to the questions.
Answer: The scientific method is a systematic approach used by scientists to investigate and understand the natural world. It consists of several steps that help to ensure objectivity, accuracy, and reliability in the process of scientific inquiry.
It's important to note that the scientific method is an iterative process, meaning that scientists often repeat steps and refine their approach based on new information and insights gained from previous experiments. This helps to build a stronger understanding of the natural world and contributes to the development of scientific knowledge.
Explanation:
1. Observation: The scientific method begins with making careful observations about a phenomenon or event. This could involve gathering data, conducting experiments, or examining existing information.
For example, let's say you notice that plants in your garden are growing taller when they receive more sunlight.
2. Research: Once an observation is made, scientists conduct research to gather information and background knowledge related to the phenomenon they are studying. This can involve reviewing existing studies, reading scientific literature, or consulting experts in the field.
In our example, you might research how sunlight affects plant growth and find relevant studies on the topic.
3. Hypothesis: After conducting research, scientists develop a hypothesis, which is a tentative explanation or prediction for the observed phenomenon. The hypothesis should be testable and based on the available evidence.
In our example, a hypothesis could be that increased exposure to sunlight promotes plant growth due to the role of sunlight in photosynthesis.
4. Experimentation: To test the hypothesis, scientists design and carry out experiments. This involves carefully controlling variables and collecting data to analyze and draw conclusions from.
In our example, you might set up an experiment where you expose different groups of plants to varying amounts of sunlight and measure their growth over a period of time.
5. Analysis: Once the data is collected, scientists analyze it using statistical methods to determine if the results support or refute the hypothesis. This analysis helps to draw meaningful conclusions from the experiment.
In our example, you would analyze the data collected from the different groups of plants to see if the ones exposed to more sunlight indeed grew taller.
6. Conclusion: Based on the analysis of the data, scientists draw conclusions about the hypothesis. If the results consistently support the hypothesis, it may be considered valid. If not, scientists may revise the hypothesis and repeat the process.
In our example, if the plants exposed to more sunlight consistently grew taller, it would support the hypothesis that increased sunlight promotes plant growth.
A rock is thrown at an angle of 30 degrees above the horizontal with initial velocity 15m/s what is the displacement when the rock returns to the ground
The displacement of the rock will be the same as the total horizontal distance traveled. Here the rock's horizontal position is given by
[tex]x=\left(15\,\dfrac{\mathrm m}{\mathrm s}\right)\cos30^\circ\,t[/tex]
so to find the horizontal distance it traversed, we need to know the time it took for the rock to return to the ground. We use the rock's vertical position over time to figure that out:
[tex]y=\left(15\,\dfrac{\mathrm m}{\mathrm s}\right)\sin30^\circ\,t-\dfrac g2t^2=0[/tex]
where [tex]g=9.8\,\dfrac{\mathrm m}{\mathrm s^2}[/tex] is the acceleration due to gravity. Then we find that [tex]t\approx1.5\,\mathrm s[/tex], at which point we find [tex]x\approx20\,\mathrm m[/tex].
Amy uses 20n of force to push a lawn mower 10 meters. How much work does she do
What was the Great Dark Spot of Neptune?
A. an area with a high concentration of methane
B. a shadow cast by a nearby dwarf planet
C. a windy and powerful storm system
D. a pool of water on the planet's surface
C. a windy and powerful storm system
C. a windy and powerful storm system
A cylindrical block of aluminum has a radius 2.5 cm and
length 20 meters. The center of the cylinder has 20 mm of
aluminum removed radially
(A) What is the resistance of this block of material?
(B) What temperature would the aluminum have to be at to have the
same resisttivity as tungsten of the same size and length?
C) How much power is dissipated when 30 amps of is passed through
the cylindrical block using the resistance from part A.
(A) The resistance of the block of aluminum is given by:
[tex]R=\frac{\rho L}{A}[/tex]
where
[tex]\rho[/tex] is the aluminum resistivity
L is the length of the cylinder
A is the cross-sectional area of the cylinder
We already know the aluminum resistivity ([tex]\rho=2.65 \cdot 10^{-8} \Omega m[/tex]) and the length of the cylinder (L=20 m), so we must find the cross-sectional area A, which is given by the difference between the area of the larger cylinder and the area of the radial hole:
[tex]A=\pi (R^2 -r^2)[/tex]
where [tex]R=2.5 cm=0.025 m[/tex] and [tex]r=20 mm=0.02 m[/tex] (assuming that the 20 mm removed radially refers to the radius of the hole).
Therefore, the cross-sectional area is
[tex]A=\pi ((0.025 m)^2-(0.020 m)^2)=7.06 \cdot 10^{-4} m^2[/tex]
Substituting into the initial formula of the resistance, we find:
[tex]R=\frac{\rho L}{A}=\frac{(2.65 \cdot 10^{-8} \Omega m)(20 m)}{7.06 \cdot 10^{-4} m^2}=7.51 \cdot 10^{-4} \Omega[/tex]
(B) The resistivity of the tungsten is [tex]\rho=5.6 \cdot 10^{-8} \Omega m[/tex], so a cylinder of tungsten of the same size would have a resistance of
[tex]R=\frac{\rho L}{A}=\frac{(5.6 \cdot 10^{-8} \Omega m)(20 m)}{7.06 \cdot 10^{-4} m^2}= 1.59 \cdot 10^{-3} \Omega[/tex]
The behaviour of the resistance versus temperature is given by:
[tex]R=R_0 (1 + \alpha \Delta T)[/tex]
where [tex]\alpha[/tex] is a coefficient that for aluminum is equal to [tex]\alpha = 0.004308[/tex], R0 is the resistance of the piece of aluminum we found at point (A), and R is the resistance of the tungsten. Re-arranging the formula and substituting, we find
[tex]\Delta T = \frac{R/R_0 -1}{\alpha}=\frac{\frac{1.59 \cdot 10^{-3} \Omega}{7.51 \cdot 10^{-4} \Omega}-1}{0.004308}=259.3^{\circ}C[/tex]
So, the temperature must increase by 259.3 degrees.
(C) The power dissipated is given by:
[tex]P=I^2 R[/tex]
where I=30 A is the current. Substituting the numbers into the formula, we find
[tex]P=(30 A)^2 (7.51 \cdot 10^{-4} \Omega)=0.68 W[/tex]
Why is an abseiling rope tested beyond twice the maximum possible weight when in use
ANSWER:
Abseiling rope is tested beyond twice the maximum possible weight when in use because of safety purposes.
EXPLANATION:
Every rope has its elastic limit.Abseiling rope is used basically for climbing or descending purposes so this type of rope must be of quite good quality and it must bear maximum possible weight. We test it just to check the elastic limit of the rope so that the rope shouldnot increase its elastic limit and it doesnot break when we use it.
in a free body diagram, the force arrows always point what way?
Forces are presented as straight arrows pointing in the direction they function on the body.
The force arrows always points straight arrows.
Salmon often jump waterfalls to reach their breeding grounds. Starting 3.15 m from a waterfall 0.45 m in height, at what minimum speed must a salmon jumping at an angle of 33.2 degree leave the water to continue upstream? The acceleration due to gravity is 9.81 m/s2. Answer in units of m/s.
Let the salmon jump with speed v at an angle of 33.3 degree
So here we can find out the components of his velocity in x and y direction
[tex]v_x = v cos33.2[/tex]
[tex]v_y = v sin33.2[/tex]
now the horizontal displacement of the salmon is 3.15 m so he cover this horizontal distance with constant speed as there is no acceleration in x direction
here we can say
[tex]v_x * t = 3.15[/tex]
[tex]v cos33.2 * t = 3.15[/tex]
[tex]v*t = 3.76[/tex]
now in Y direction it is an accelerated motion as it is accelerated due to gravity
[tex]y = v_y * t + \frac{1}{2}at^2[/tex]
[tex]-0.45 = v sin33.2* t - \frac{1}{2}*9.8* t^2[/tex]
now we will plug in v*t = 3.76
[tex]-0.45 = 3.76 * sin33.2 - 4.9 * t^2[/tex]
[tex]4.9 t^2 = 2.51[/tex]
[tex]t^2 = 0.512[/tex]
[tex]t = 0.72 s[/tex]
now speed v is given by equation above
[tex]v*t = 3.76[/tex]
[tex]v*0.72 = 3.76[/tex]
[tex]v = 5.25 m/s[/tex]
so here he must have to jump with minimum speed of 5.25 m/s
Type the correct answer in the box. Use numerals instead of words.
On average, how much of their income will a family spend on food?
Income level of a family is one of the factors that affect a food budget. On average, a family will spend ________percent of their income on food.
10% of the income.
Explanation:According to the most recent data from the U.S. Bureau of Labor Statistics, in 2013 the average American household spent about 10% of its total budget on food.For example if you have income of $6000, you will spend $600 on food.Answer:
20% of their income
Explanation:
I got a five on Plato
to improve the acoustics in an auditorium, a sound reflector with a mass of 170kg is suspended by a chain from the ceiling. what is the tension in the chain? assume that the mass of the chain itself is 8.0kg.
Mass of the sound reflector is given as
[tex]m_1 = 170 kg[/tex]
mass of the chain itself is
[tex]m_2 = 8 kg[/tex]
now here since this system is suspended at rest and no acceleration is given for the system so in order to find the tension in the chain we will just use force balance equation
As per force balance we can say that weight of the chain and reflector downwards will be counter balanced by tension in the string
Now here we will have
[tex]T = m_1g + m_2g[/tex]
since chain is given with some mass so tension at the top end of the chain will be
[tex]T = 170* 9.8 + 8 * 9.8[/tex]
[tex]T = 1744.4 N[/tex]
So here tension in the chain will be 1744.4 N at the top end and this tension will decrease as we move down along the length of the chain.
a kangaroo is capable of jumping to a height of 2.62 m. determine the takeoff speed of the kangaroo.
a) 717
b) 8.2
c) 5.92
d) 7.17
kangaroo is capable of jumping to a height of 2.62 m
It means it will reach maximum height of 2.62 m when it will jump off with some maximum capable speed from the ground
So here as it will reach to its maximum height the final speed of the kangaroo will be zero
and also we know that during the motion of kangaroo the acceleration of kangaroo is due to gravity which is given by g = 9.8 m/s^2
now we can use kinematics equation to find out take off speed
[tex]v_f^2 - v_i^2 = 2 a d[/tex]
here we know that
[tex]v_f = 0[/tex]
a = - 9.8 m/s^2
d = 2.62 m
now we will have
[tex]0^2 - v_i^2 = 2 * (-9.8)* 2.62[/tex]
[tex] - v_i^2 = - -51.352 [/tex]
[tex]v_i = \sqrt{51.352}[/tex]
[tex]v_i = 7.17 m/s[/tex]
so the take off speed of the kangaroo will be 7.17 m/s and correct answer is "option d"
Answer:
vi = 7.17 m/s
Explanation:
(4225 m2/s2)/(6 m/s2) = d
d = 704 m
Return to Problem 8
Given:
vi = 22.4 m/s
vf = 0 m/s
t = 2.55 s
Find:
d = ??
d = (vi + vf)/2 *t
d = (22.4 m/s + 0 m/s)/2 *2.55 s
d = (11.2 m/s)*2.55 s
d = 28.6 m
Return to Problem 9
Given:
a = -9.8 m/s2
vf = 0 m/s
d = 2.62 m
Find:
vi = ??
vf2 = vi2 + 2*a*d
(0 m/s)2 = vi2 + 2*(-9.8 m/s2)*(2.62 m)
0 m2/s2 = vi2 - 51.35 m2/s2
51.35 m2/s2 = vi2
vi = 7.17 m/s
A scientific law is?
Scientific law is also known as natural law. It imply a cause and effect between the observed elements and always apply under the same conditions .
Scientific law is a statement based on repeated experimental observations that describes some aspect of the Universe.
The term law has diverse usage in many cases (approximate, accurate, broad, or narrow theories) across all fields of natural science (physics, chemistry, biology, geology, astronomy, etc.). Scientific laws summarize and explain a large collection of facts determined by experiment.A scientific law always applies under the same conditions, and implies that there is a causal relationship involving its elements.What is the x-component of vector E⃗ of the figure in terms of the angle θ and the magnitude E?
The x-component of a vector can be calculated using the magnitude of the vector and the angle it forms with the positive x-axis.
Explanation:In a rectangular coordinate system in a plane, the x-component of a vector is given by the dot product of the vector with the unit vector Î (î). The x-component can be calculated as:
Ex = E * cos(θ)
where E is the magnitude of the vector and θ is the angle the vector forms with the positive x-axis.
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The x-component of a vector describes the part of the vector in the x direction. In the case of vector E⃗, it can be computed based on the angle θ it makes with the x-axis and its magnitude E through the relationship E cosθ.
Explanation:The x-component of a vector describes the effect of the vector in the 'x' direction. This can be visualized by understanding that any vector can be viewed as a resultant of its components along the various axes available (here, along 'x'). Thus, when a given vector is expressed in rectangular or Cartesian components, the respective projections of the vector on 'x' (and 'y') directions essentially give the x-component (and y-component).
In the case of vector E⃗, the x-component can be computed based on the angle θ (theta) it makes with the 'x' axis and its overall magnitude E, using simple trigonometric principles. The x-component (Ex) is given by E cosθ because cosθ gives the fraction of the magnitude E that lies along the 'x' direction.
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The diagram shows Ned’s movement as he left his house and traveled to different places throughout the day. Which reference point should be used to find out how far Ned traveled when he went from the pet store to the swimming pool?
The pet store would be the reference point because it is where he started and it will not move. Hope this helped.
The pet store would be the reference point because it is where he started motion and it will not move.
What is motion?The phenomenon of an item changing its position with respect to time is known as motion in physics. In mathematics, displacement, distance, velocity, and acceleration are used to explain motion.
A reference point is a location or object that is used as a point of comparison to ascertain whether something is moving. When an object shifts in relation to a fixed point, it is said to be in motion. Good reference points are things that are fixed in relation to Earth, like a building, a tree, or a sign.
The pet store would be the reference point because it is where he started motion and it will not move.
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What is the most important concern when trying to prevent frostbite?
A. Drinking enough fluids
B.wearing cotton next to your skin
C. Dressing to protect hands
D.wearing sunscreen
answer is C. dressing to protect hands
sara and tory are out fishing on the lake on a hot summer day when they both decide to go for a swim. sara dives off the front of the boat with a force of 45° N, while Tory dives off the back of the boat with a force of 60° N. Draw a vector diagram of the situation. Find the resultant force on the boat.
Here it is an application of Newton's III law
as we know by Newton's III law that every action has equal and opposite reaction
So here as we know that two boys jumps off the boat with different forces
from front side of the boat the boy jumps off with force 45 N which means as per Newton's III law if boy has a force of 45 N in forward direction then he must apply a reaction force on the boat in reverse direction of same magnitude
So boat must have an opposite force on front end with magnitude 45 N
Now similar way we can say
from back side of the boat the boy jumps off with force 60 N which means as per Newton's III law if boy has a force of 60 N in backward direction then he must apply a reaction force on the boat in reverse direction of same magnitude
So boat must have an opposite force on front end with magnitude 60 N
So here net force due to both jump on the boat is given by
[tex]F_{net} = F_1 - F_2[/tex]
[tex]F_{net} = 60 - 45[/tex]
[tex]F_{net} = 15 N[/tex]
so boat will have net force F = 15 N in forward direction due to both jumps
How do you know that a sealed calorimeter is a closed system? Because the temperature is conserved Because the masses of the sample and water are equal Because the thermal energy is not transferred to the environment Because the work is done on the test sample
Answer: A sealed calorimeter is a closed system because thermal energy is not transferred to the environment.
A closed system is an isolated system where there is no transfer of energy with its surroundings. Also the system is not subjected to any external force whose source is external to the system.
Answer:C. Because thermal energy has not transferred to the environment.
Explanation:
A motorcycle traveling at 25 m/s accelerates ya a rate of 7.0 m/s2 for 6.0 seconds. What is the final velocity of the motorcycle?
First write down all your known variables:
vi = 25m/s
a = 7.0m/s^2
t = 6.0s
vf = ?
Then choose the kinematic equation that relates all the variables and solve for the unknown variable:
vf = vi + at
vf = (25) + (7.0)(6.0)
vf = 67m/s
The final velocity of the motorcycle is 67m/s.
if 2 objects have the same momentum which statement is true
A.mass and velocity are the same for both
B.they both have the same mass
C.the product of mass x velocity is the same for both
D.they both have the same velocity
C is the correct option
As momentum = (mass) (velocity)
P=mv
So the object having greater mass has less velocity and the object having smaller mass will move faster. But product of mass and velocity is same to each other.
Explain the versatility of epithelial tissue
Answer:
Explanation:
The epithelial tissues cover the body surfaces, forms a lining over the body cavities and hollow organs. These tissues also forms a protective barrier between the external environment and the body.
The epithelial tissues are the tissues which performs various functions. These tissues are composed of cells that are laid close to each other with the cells that lies in the close association with each other. The structure and function of the epithelial cells vary from both upper and lower surfaces. Due to variety in the functions of the epithelial tissues like protection, secretion, cellular transportation, filtration, selective absorption and sensing, these are called as the versatile tissues.
Why is the law of gravity an example of a universal law?
A) gravity is the attraction of any mass to any other other mass .
B) Gravity is a force that affects everyone on earth
C) gravity is the reason the earth revolves around the sun
D) gravity is a force that exist between any two masses in the universe
A) gravity is the attraction of any mass to any other other mass .
D) gravity is a force that exist between any two masses in the universe
both are ok ...
A block has a volume of 0.09m3 and a density of 4000kg/m3. What's the force of gravity acting on the block in water
Volume=0.09m³
Density=4000kg/m³
Force=?
Density=mass/volume ⇒mass=volume×density
m=0.09×4000=360kg
Force=mass×accelaration
F=360×9.8
F=3528N
Answer
3,528 N
Explanation
density = mass/volume
ρ = m/v
∴ m = ρv
= 4000 × 0.09
= 360 Kg
Weight is defined as the force that acts on a body and is directed towards the center of the earth.
Weight = mass × acceleration due to gravity
W = mg Where g = 9.8 m/s²
W = 360 × 9.8
= 3,528 N
If a person is standing still in a moving elevator at 55 mph what is her speed in mph relative to the elevator
We are standing still inside an elevator
So our speed in the frame of elevator is zero
we can write this relative speed as
[tex]v_{pE} = v_p - v_E[/tex]
also we know that speed of the elevator is 55 mph
[tex]v_E = 55 mph[/tex]
now the velocity in relative frame is zero as he is still in the moving elevator while in the ground frame or observing from the ground its velocity will be same as velocity of elevator.
So whenever an object is at rest in a moving frame then its relative velocity with respect to that frame must be ZERO
Across what potential difference does an electron have to be accelerated in order to reach the speed v=3e7 m/s?
When an electron is accelerated through potential difference then the speed that it attain will be explained by energy conservation
here by energy conservation we can say that
change in kinetic energy of electron = electrostatic potential energy gained through given potential difference
kinetic energy is given as
[tex]KE = \frac{1}{2}mv^2[/tex]
electrostatic potential energy is given as
[tex]PE = qV[/tex]
now by energy conservation
[tex]qV = \frac{1}{2}mv^2[/tex]
given that for electron
[tex]m = 9.1 * 10^{-31} kg[/tex]
[tex]v = 3 * 10^7 m/s[/tex]
[tex]q = 1.6 * 10^{-19} C[/tex]
now by plug in values
[tex]1.6 * 10^{-19} * V = \frac{1}{2}*9.1* 10^{-31} *(3*10^7)^2[/tex]
[tex]V = \frac{4.095 * 10^{-16}}{1.6 * 10^{-19}}[/tex]
[tex]V = 2559.4 Volts[/tex]
So here it is accelerated through potential difference of 2559.4 Volts
The electric potential is 4100 V or 4.1kV.
We know that the kinetic energy of the moving electron is equal to the 1/2mv^2. On this basis, we can write;
1/2mv^2 = eV
Where;
m = mass of the electron
v = speed of the electron
V = potential of the electron
e = charge on the electron.
Hence;
V = 1/2mv^2 /e
V = 0.5 × 9.11 × 10^-31 × (3 × 10^7)^2/1.6 ×10^-19
V = 4100 V or 4.1kV
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You are driving up an inclined road. After 2.4km you notice a roadside sign that indicates that your elevation has increased by 160m. What is the angle of the road above the horizontal?
The 'slope' of the road is (rise between two points) / (hotizontal distance between the same two points). Or (rise)/(run). It's also the tangent of the angle between the horizontal and the incline.
In this problem, your 'run' is 2.4 km, and the 'rise' is 160 m.
The slope of the incline is (160) / (2,400) .
That's 0.0667 .
To answer the question, you need to find the ANGLE whose tangent is that same number.
If your calculator has ANY functions on it, then " tan⁻¹ " is the one you want. Key in a number, and " tan⁻¹ " will give you the angle whose tangent is that number.
The angle of the road above the horizontal is found using trigonometry, specifically the tangent function, which is the ratio of the elevation gain to the distance traveled along the road. By applying the arctan function to 160m/2400m, we can calculate the angle of inclination in degrees.
Explanation:The question involves finding the angle of the road above the horizontal when the elevation change and the distance traveled along the road are known. This requires the use of trigonometry to determine the angle, given the rise (elevation change) and run (distance traveled along the road).
To find the angle, we can use the tangent function, which is the ratio of the opposite side to the adjacent side in a right triangle. In this scenario, the rise is 160 m and the run is 2400 m (2.4 km). We need to convert the run into meters to match the units of the rise, making the run 2400 m.
Now we compute the angle θ:
Rise (opposite side) = 160 mRun (adjacent side) = 2400 mTangent of θ = Rise / Run = 160m / 2400mTan θ = 1/15θ = arctan(1/15)Once we calculate the arctan(1/15), we will get the angle of inclination of the road in degrees.
The chart shows data for four heat engines.
Which lists the engines from most efficient to least efficient?
Y, X, W, Z
Z, W, X, Y
Z, X, W, Y
Y, W, X, Z
efficiency of the heat engine is calculated by the formula
[tex]\eta = 1- \frac{T_c}{T_h}[/tex]
here we know that
[tex]T_c [/tex] = cold temperature
[tex]T_h [/tex] = hot temperature
now we will find the efficiency of all
1) for W
[tex]\eta_1 = 1- \frac{T_c}{T_h}[/tex]
[tex]\eta_1 = 1- \frac{120}{620}[/tex]
[tex]\eta_1 = 0.806[/tex]
2) for X
[tex]\eta_2 = 1- \frac{T_c}{T_h}[/tex]
[tex]\eta_2 = 1- \frac{100}{840}[/tex]
[tex]\eta_2 = 0.88[/tex]
3) For Y
[tex]\eta_3 = 1- \frac{T_c}{T_h}[/tex]
[tex]\eta_3 = 1- \frac{300}{900}[/tex]
[tex]\eta_2 = 0.67[/tex]
4) for Z
[tex]\eta_4 = 1- \frac{T_c}{T_h}[/tex]
[tex]\eta_4 = 1- \frac{25}{500}[/tex]
[tex]\eta_4 = 0.95[/tex]
So here most efficient engine is Z and least is Y
so we can arrange it as
Z > X > W > Y
so 3rd option is correct here
Answer:
C.) Z, X,W, Y
A hiker walks 3.3km at an angle of 40 degrees north of west. Then, the hiker walks 3.4km at an angle of 60 degrees north of west. What is the hiker's total displacement
Answer
6.6 km
The description of the problem is shown in the attached figure, where the line "d" represents the final displacement vector.
First, the trekker walked 3.3km in a 40 ° direction, as shown in the figure. We can write this vector in its Cartesian coordinates:
[tex]-3.3sin (40)x + 3.3cos (40)y[/tex]
Then the hiker walked 3.4 km in a 60 degree northwest direction.
We can write this as a vector in its Cartesian coordinates:
[tex]-3.4sin (60)x + 3.4cos (60)y[/tex].
When adding this two vectors we will obtain the final displacement "d"
[tex]d = [- 3.3sin(40) -3.4sin (60)]x + [3.3cos(40) + 3.3cos (60)]y\\[/tex]
[tex]d = -5.07x +4.23y\\[/tex]
To obtain the magnitude of this vector we calculate its module:
[tex]\sqrt{5.07 ^2 +4.23 ^ 2}[/tex]
Then the magnitude of the final displacement was:
6.6 km
Help? Will give thanks if right (thank you)
Salmon often jump waterfalls to reach their breeding grounds. Starting 3.15 m from a waterfall 0.45 m in height, at what minimum speed must a salmon jumping at an angle of 33.2 degree leave the water to continue upstream? the acceleration due to gravity is 9.81 m/s2. Answer in units of m/s.
Let the salmon jump with speed v at an angle of 33.3 degree
So here we can find out the components of his velocity in x and y direction
[tex]v_x = v cos33.2[/tex]
[tex]v_y = v sin33.2[/tex]
now the horizontal displacement of the salmon is 3.15 m so he cover this horizontal distance with constant speed as there is no acceleration in x direction
here we can say
[tex]v_x * t = 3.15[/tex]
[tex]v cos33.2 * t = 3.15[/tex]
[tex]v*t = 3.76[/tex]
now in Y direction it is an accelerated motion as it is accelerated due to gravity
[tex]y = v_y * t + \frac{1}{2}at^2[/tex]
[tex]-0.45 = v sin33.2* t - \frac{1}{2}*9.8* t^2[/tex]
now we will plug in v*t = 3.76
[tex]-0.45 = 3.76 * sin33.2 - 4.9 * t^2[/tex]
[tex]4.9 t^2 = 2.51[/tex]
[tex]t^2 = 0.512[/tex]
[tex]t = 0.72 s[/tex]
now speed v is given by equation above
[tex]v*t = 3.76[/tex]
[tex]v*0.72 = 3.76[/tex]
[tex]v = 5.25 m/s[/tex]
so here he must have to jump with minimum speed of 5.25 m/s
If a car went 30 km West I’m 25 min. And then 40 km south in 35 min. What would be it’s average
Its average would be 35km in 30 minutes Hope this helps :D
Which is an effect of gravity on objects on the surface of Earth? Check all that apply.
• Objects “fall” toward the center of Earth.
• Objects are pulled by Earth but do not pull on Earth.
• Objects accelerate at a rate of 9.8 m/s each second.
• Objects travel at a rate of 9.8 m/s to are the center of Earth.
• Objects are pulled by Earth more strongly than they pull on Earth.
• Objects “fall” toward the center of Earth. (TRUE)
Since the gravitational force between earth and any object is always along the line joining the centers of two so all the objects near the surface of earth will always feel force towards the centre of the earth due to gravity.
• Objects are pulled by Earth but do not pull on Earth. (FALSE)
Since gravitational force will always follow Newton's III law as per which every action has equal and opposite reaction force so object near the surface of earth will also pull the earth as earth is pulling the object towards the center.
• Objects accelerate at a rate of 9.8 m/s each second. (TRUE)
Since acceleration due to gravity of Earth is 9.8 m/s^2 so here we can say that all objects near the surface of earth will accelerate towards the center of earth at rate of 9.8 m/s^2 due to gravitational pull.
• Objects travel at a rate of 9.8 m/s to are the center of Earth. (FALSE)
Since earth is pulling all objects near its surface with gravitational force so objects can not move at constant speed but it will move with constant acceleration.
• Objects are pulled by Earth more strongly than they pull on Earth. (FALSE)
Since gravitational force will always follow Newton's III law which say every action has equal and opposite reaction so we can say that force due to all objects on earth will be same as the force of earth on the object.