a student attaches a rope to a 20.0 kg box of books. he pulls with force of 90.0 n at a angle of 30.0° with the horizontal. the coefficient of kinetic friction between the box and the sidewalk is 0.500. find the acceleration of the box

Gasoline fuel is a renewable alternative to petroleum fuels that is made through either biologically or chemically driven production in a process called gasification.

Answer:

Hydrogen fuel is a renewable alternative to petroleum fuels that is made through either biologically or chemically driven production in a process called gasification.

As per Newton's II law we can say force applied on an object is product of mass and acceleration

[tex]F = ma[/tex]

given that

Force = 140 N

mass = 32.5 kg

now we can use above formula

[tex]140 = 32.5* a[/tex]

[tex]a = \frac{140}{32.5}[/tex]

[tex]a = 4.31 m/s^2[/tex]

so its acceleration must be 4.31 m/s^2

The mass of the baking soda was 80 g

Answer: the mass is 80g

Explanation: In a solution of 140g, we knot that there are 60g of vinegar, the only other component in the solution is baking soda.

Now we want to find the mass of the baking soda in the solution.

Because there are only two components in the solution, if we remove the 60g of vinegar, the residue mass is the mass of the baking soda.

then we need to calculate:

Mass = 140g - 60g = 80g

So the mass of baking soda in the solution is 80g.

Pascal's law (also Pascal's principle or the principle of transmission of fluid-pressure) is a principle in fluid mechanics that states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere.

Answer: The pressure at two pistons within an enclosed fluid system is always the same.

Explanation:

Answer

The answer to this question is [tex]30 ms^{-1}[/tex]

Explanation

As we know that accelartion is the rate of change of velocity. So, it can be write as

[tex]a = (V_f -V_i) /t[/tex]

where

[tex]V_f[/tex] is the final velocity

[tex]V_i[/tex] is the initial velocity

t is the time

a is the accelartion

as we konw

[tex]a = 3 ms^{-2}[/tex]

t = 10 s

From rest So,

[tex]V_i[/tex] = 0

[tex]V_f[/tex] = ?

Putting values

[tex]3 = (V_f - 0)/10[/tex]

[tex]3 * 10 = V_f[/tex]

[tex]30 = V_f[/tex]

[tex]V_f = 30 ms^{-1}[/tex]

So, the right answe is [tex]30 ms^{-1}[/tex]

(3 m/s²) x (10 s) = 30 m/s

His speed at the end of 10 sec is 30 m/s.  We can't describe his velocity, because we have no information about the direction he's moving.

The primary energy exhibited is:

friction:  Heat energy

Due to friction. there is heat loss in mostly all machines.

nuclear power plant:  Nuclear energy

In nuclear power plant, fission or fusion of radio-active substances produces large amount of nuclear energy.

toaster element:  Heat energy

Heat energy is produced in the toaster when electricity passes through the element. This is used to heat the toasts.

welding torch:  Heat energy

The heat energy produced in the welding torch is used in welding.

eraser sitting on a desk edge:  Potential energy

Potential energy is possessed by a body due to virtue of its height.

light bulb:  Heat energy and light energy.

The element inside the bulb gets heated first and then light energy is produced.

campfire:  Heat energy

Heat is produced and then light energy in case of campfire.

moving car:  Kinetic energy

A moving body has kinetic energy.

lump of coal in a storage bin:  Potential energy

A lump of coal in a storage bin has potential energy.

stick of TNT: potential energy

Stick of TNT is formed of explosive mixture. It contains potential energy.

Answer:

• Friction ( heat )

• Nuclear power plant ( nuclear )

• Toaster element ( heat )

• welding torch ( heat )

• eraser sitting on a desk edge (potential)

• light bulb ( light )

• campfire ( heat )

• moving car ( kinetic )

• lump of coal in a storage bin ( potential )

• stick of tent ( potential)

Explanation: hope this helps !

Time before projectile hits wall

= 88.2 m / 29.4 m/s = 3 seconds

Vertical velocity of projectile after three seconds

= 3*9.8 = 29.4 m/s

Horizontal velocity of projectile after three seconds, assuming no air resistance

= 29.4 m/s  (given)

Conclusion:

velocity of projectile when it hits the wall

= < 29.4, -29.4> m/s

= sqrt(29.4^2+29.4^2) m/s east-bound at 45 degrees below horizontal

= 41.58 m/s east-bound at 45 degrees below horizontal.

Final answer:

The projectile's velocity when it strikes the wall is a combination of its initial horizontal velocity and the vertical velocity it gains due to gravity. The horizontal velocity remains constant at 29.4 m/s east, but the final velocity also includes a downward vertical component due to gravity. The exact final velocity would require calculating the vertical component at impact but is not simply 29.4 m/s east.

Explanation:

The question is a classic example of a projectile motion problem in physics, specifically dealing with a projectile launched horizontally. The key concept here is that horizontal motion and vertical motion are independent of each other. Since the projectile is launched horizontally at a speed of 29.4 m/s without any initial vertical component, this speed will not change throughout its flight because horizontal velocity remains constant when neglecting air resistance. The vertical motion of the projectile, however, is influenced by gravity, which causes it to accelerate downwards at 9.8 m/s2.

To find the velocity at the moment it strikes the wall, we need to separately consider the horizontal and vertical components of velocity. The horizontal component remains 29.4 m/s east, as stated. To find the vertical component, we need to calculate the time it takes for the projectile to reach the wall. This is done by dividing the horizontal distance by the horizontal velocity (time = distance / velocity = 88.2 m / 29.4 m/s).

Without calculating the exact time here, it's important to understand that by the time it hits the wall, the projectile has gained a vertical velocity component due to gravity. The final velocity is a vector combination of the horizontal and vertical components. Therefore, the answer is not simply 29.4 m/s east, as that disregards the vertical component. The exact answer would involve calculating the vertical velocity at the time of impact and then combining it with the horizontal velocity to find the magnitude and direction of the final velocity vector. Options A, C, and D involve assumptions or calculations not fully provided here, but the question's premise indicates that the projectile's velocity upon impact is a combination of both horizontal and vertical components.

here tennis ball is accelerated from initial speed zero to final speed 50 m/s

In this accelerated motion the distance moved by the ball is 0.5 m

So here we can use kinematics to find the acceleration of the ball during this distance

[tex]v_f^2 - v_i^2 = 2 a d[/tex]

here given that

vf = 50 m/s

vi = 0

d = 0.5 m

[tex]50^2 - 0 = 2*a*0.5[/tex]

[tex]2500 m/s^2 = a[/tex]

now if we have acceleration during its motion so we can find the applied force by using Newton's II law

[tex]F = ma[/tex]

[tex]F = 0.06*2500[/tex]

[tex]F = 150 N[/tex]

now the applied force will be 150 N on the ball by racket

Kinetic energy of anything is (1/2) (mass) (speed)² .

Your kinetic energy just before you snap back up (? ?) is

(1/2) (your mass in kilograms) (50 m/s)² =

(1/2) (your mass in kilograms) (2,500 m²/s²) =

(1,250 x your mass in kilograms) .  The unit is Joules.

Answer:

 Length of displacement vector = 7.51 m

Explanation:

 Consider east as positive X axis and North as positive Y axis.

 Eric headed 6 meters east, Displacement = 6 i

 Then he headed X meters north, Displacement = X j

 Total displacement = 6 i + X j

  Angle it makes with horizontal axis, θ = tan⁻¹(X/6) = 37°

  X/6 = tan 37

   X = 4.52 m

Total displacement = 6 i + 4.52 j

Magnitude = [tex]\sqrt{6^2+4.52^2} =7.51m[/tex]

 Length of displacement vector = 7.51 m

The answer is A. 7.5.

given that initial speed of the car is

[tex]v_i = 8.9 m/s[/tex]

now after travelling the distance d = 1.8 * 10^1 m the car will stop

so here we can use kinematics to find the acceleration of car

[tex]v_f^2 - v_i^2 = 2 a d[/tex]

[tex]0 - 8.9^2 = 2 a d[/tex]

here we have

[tex]- 79.21 = 2*(18)*a[/tex]

[tex]a = -2.2 m/s^2[/tex]

net force applied due to brakes of car is given by Newton's II law

[tex]F = ma[/tex]

here we have

mass = 1.2 * 10^3 kg

[tex]F_{net} = 1.2 * 10^3 * 2.2[/tex]

[tex]F_{net} = 2.64 * 10^3 N[/tex]

now we can say

[tex]F_{net} = F_1 + F_2[/tex]

[tex]2.64 * 10^3 = 1.8 * 10^3 + F_2[/tex]

[tex]F_2 = 8.4 * 10^2 N[/tex]

So the force applied due to brakes is given as above

-- reduce the length of a wire to 1/2 . . . cut the resistance in half

-- reduce the diameter to 1/4 . . . reduce the cross-section area by (1/4²) . . . increase the resistance by 16x .

-- R2 = (R1) · (1/2) · (16)  =  8 · R1

-- R2 / R1  =  8

Tension in the rope due to applied force will be given as

[tex]F = 142 N[/tex]

angle of applied force with horizontal is 37 degree

displacement along the floor = 6.1 m

so here we can use the formula of work done

[tex]W = F d cos\theta[/tex]

now we can plug in all values above

[tex]W = 142 * 6.1 * cos37[/tex]

[tex]W = 691.8 J[/tex]

So here work done to pull is given by 691.8 J

The answer is C because only the bottom has the water pressure applied to it because it's the only thing emersed in the water.

The pressure on a brick that is totally immersed in water, with the long edge of the brick vertical is: C. greatest on the bottom of the brick.

Pressure can be defined as a measure of the external force acting upon a surface area. Mathematically, the pressure acting on an area is given by the formula:

[tex]Pressure = \frac{Force}{Area}[/tex]

In this scenario, the pressure on the brick with a long, vertical edge, that is totally immersed in water is greatest on its bottom because the long, vertical edge displaces water.

Read more: https://brainly.com/question/22480179

Answer:

THE ANSWER IS D

Explanation:

I DID THE TEST

Given:

Time taken for the travel: 40 mins=2400 secs

Velocity: 1.2m/s

Speed and velocity have the same magnitude. Speed is a scalar where as velocity is a vector quantity.

Distance traveled= speed x time.

Distance traveled: 1.2 x 2400=2880m

C. About the same amount of time to hit the floor.

I just took a test with this question and got it right :)

Hope this is helpful.

Option C :- about the same amount of time to hit the floor

Because Mass has no effect on how fast things travel  in free fall situations . If you look at your kinematics equations  none of them consider mass as a variable.

however mass does have effect on energy.

Answer:

the is answer is Static friction took the test its right.

Explanation:

Object true weight is given as

[tex]mg = 123 N[/tex]

now we know that g = 9.8 m/s^2

[tex]m* 9.8 = 123 [/tex]

[tex] m = \frac{123}{9.8} = 12.55 kg[/tex]

now when it is complete submerged in water its apparent weight is given as 82 N

apparent weight = weight - buoyancy force

apparent weight = 82 N

weight = 123 N

now we have

82 = 123 - buoyancy force

buoyancy force = 123 - 82 = 41 N

now we also know that buoyancy force is given as

[tex]F_b = p_{liq}Vg[/tex]

[tex]41 = 1000*V*9.8[/tex]

[tex]V = \frac{41}{1000*9.8}[/tex]

[tex]V = 4.18 * 10^{-3} m^3[/tex]

now as we know that mass of the object is 12.55 kg

its volume is 4.18 * 10^-3 m^3

now we know that density will be given as mass per unit volume

[tex]density = \frac{m}{V}[/tex]

[tex]density = \frac{12.55}{4.18*10^{-3}[/tex]

[tex]density = 3002.4 kg/m^3[/tex]

so here density of object is 3002.4 kg/m^3

Answer:

3000 kg/m^3

Explanation:

True weight = weight in air = 123 N

Apparent weight = weight in water = 82 N

Loss in weight of the object = true weight - apparent weight

Loss in weight = 123 - 82 = 41 N

According to the Archimedes principle, the loss in weight of the object is equal to the buoyant force acting on the object.

Let V be the volume of the object an d be the density of the object.

Buoyant force = volume of the object x density of water x gravity

41 = V x 1000 x g

[tex]V = \frac{41}{1000 g}[/tex]       .... (1)

Now, true weight = Volume of the object x density of object x gravity

[tex]123 = \frac{41}{1000 g} \times d\times g[/tex]      from (1)

d = 3000 kg/m^3

(D) decreases, inverse

Average speed of a body is defined as the ratio of the distance traveled to the time taken to travel the distance. The runner runs the same distance  of 400 m during each lap but takes 5 seconds more for each lap.

Since [tex]v_a_v_g=\frac{d}{t}[/tex], as time increases, the average speed for each lap increases.

Thus, [tex]v\alpha \frac{1}{t}[/tex] when the distance traveled is the same. This is an example of an inverse proportionality relationship.

To convert a quantity in kilograms to pounds, you simply multiply by 2.2 lb/kg.

(7 kg)(2.2 lb/kg) = 15.4 lb.

Final answer:

A 7.0 kilogram bowling ball on Earth's surface weighs approximately 15.4 pounds, calculated using the conversion factor where 1 pound is equivalent to 0.4536 kilograms.

Explanation:

To convert the mass of a 7.0 kilogram bowling ball to its weight in pounds on Earth's surface, we utilize the fact that 1 pound (lb) is equivalent to 0.4536 kilograms (kg) on Earth.

The conversion from kilograms to pounds can be calculated using the ratio method:

Therefore, for a 7.0 kg bowling ball:

Thus, a bowling ball with a mass of 7.0 kg on Earth's surface has an approximate weight of 15.4 pounds.

Answer:

analyzing what data means

diagram showing the correlation between two quantities

Explanation:

Graph is the plot of two physical quantities and it describes the relation between both quantities. It gives a specific relation between the two physical quantities which is used to analyze the result.

Thus, the following options are correct,

analyzing what data means

diagram showing the correlation between two quantities

Answer: Analyzing what data means, diagram showing the correlation between two quantities, and predicting outcomes and patterns.

The first, third, and forth.

That would be balanced.

The force he applies on himself is balanced force.

The "waning gibbous" begins immediately after the Full Moon and lasts about a week.

At the end of the week, the moon is no longer gibbous, but it's still waning.  At the instant it's exactly half-illuminated, it's called "Third Quarter", and then it continuous to wane for another week.

So 3 to 4 days after the END of the waning gibbous phase, it's a Waning Crescent. It still has another 3 to 4 days of waning to go, before it wanes away to nothing and we have the next New Moon.

The waning gibbous phase is the phase between the full and last quarter moon late at night or in the early morning . The waning crescent is the phase that occurs 3-4 days later a waning gibbous.

The waning gibbous phase is the phase between the full and last quarter moon late at night or in the early morning.

The waning gibbous phase moon appears more than half-lighted but less than the full moon. A full sunset is a time when the full moon rises. The rising time of the waning gibbous moon is late at night.

It looks red like a  full moon when it’s near the horizon.

To learn more about the waning gibbous refer to the link ;

https://brainly.com/question/15045629

mass of car =700kg

Required acceleration =5m/s^2

According to newton's second law

F=ma

F=(700)(5)

F=3500 Kgm/sec^2

Answer:3500

Explanation: mass of car =700 kg

Required acceleration =5 m/s^2

According to newton's second law

F=ma

F=(700)(5)

F=3500 K gm/sec^2

time for which Jill and Scott both traveled is 30 min

as we know that

1 hour = 60 min

now we will convert the time of travel from minutes to hour

[tex]t = \frac{30 min}{60 min}* 1 hour[/tex]

[tex]t  = 0.5 hour[/tex]

now we will have to find the speed of both

For speed we know the formula

[tex]speed = \frac{distance}{time}[/tex]

speed of Jill as he cover 5 km in 30 min

[tex]v_1 = \frac{5}{0.5} = 10 km/h[/tex]

speed of Scott as he cover 10 km in 30 min

[tex]v_2 = \frac{10}{0.5}= 20 km/h[/tex]

so correct answer is

A)Scott had the faster speed since he rode at 20 k/h while Jill only traveled 10 km/h.

Speed of Jill is greater than Scott

As we know that

Speed = Distance / Time

So speed of Jill is = 5 / 0.5     since 30 minutes = 0.5 hours

Speed of Jill = 10 km/hour

And

speed of Scott is = 10 / 0.5    

Speed of Scott = 20 km/min

Here we can see that speed of Scott is greater than Jill

Answer:

C. light energy

Explanation:

In all these plants the energy is converted from the photosynthesis process. As per this photosynthesis phenomenon plants get energy by the light received from the sun.

This will help to make the plants to grow and make fruits in the plant.

in this word photosynthesis we can see it is combination of photo + synthesis

which clearly means that this energy synthesis is with the help of photons received from the sun.

These photons are light photons

So here correct answer will be

C. light energy

Answer:

light energy

Explanation:

acceleration = change in velocity/change in time

so...

a = 20 m/s / 2 seconds

a = 10

hope that helps :)

P.S. found this from Brainly User, sometimes all you have to do is search to find the answer.

i believe the answer is water vapor

hope this helps

Answer:

WATER VAPOR

Explanation:

I got a 100% on my test