A man of 60kg moves in a lift of constant velocity 5m/s .What is the reactive force acting on the man by the elevator?

​

Answer:

4 m/s

Explanation:

Momentum is conserved.

m₁ v₁ + m₂ v₂ = (m₁ + m₂) v

(50)(5) + (20)(1.5) = (50 + 20) v

v = 4

The final velocity is 4 m/s.

Answer:

D

Explanation:

Shows the distance between each new wave.

The letter in the image, that represents the wavelength or the distance traveled by the wave is letter d.

The wavelength of a wave is the distance traveled by the wave. This distance can be from one crest to another or from crest of a wave to the trough of a wave.

When the distance is between two successive crest or trough, it becomes one wavelength.

From the given image, the letter that represents the wavelength of the wave is letter d.

Learn more about wavelength here: https://brainly.com/question/10728818

The work done by the man is 35 joules. This work is only done in the horizontal direction because work is the product of force and displacement in the direction of the force.

Work done is calculated by the formula Work (W) = Force (F)  imes Distance (d)  imes cos( heta), where  heta is the angle between the force and the direction of the displacement. Since the force is in the horizontal direction and the displacement is also horizontal,  heta is 0 degrees and therefore, cos( heta) = 1. For the vertical movement, the force exerted by the man does not contribute to the work done on the weight since the displacement is perpendicular to the force applied. Hence, the work done while moving vertically is zero. The total work done is then the sum of the work done horizontally and vertically, which is 35 joules + 0 joules = 35 joules.

1. Acceleration: [tex]0.375 m/s^2[/tex]

Newton's second law states that the net force on an object is equal to the product between the object's mass and its acceleration:

F = ma

where

F is the net force

m is the mass

a is the acceleration

For the crate in this problem we have

F = 60 N

m = 160 kg

Re-arranging the equation, we can find the acceleration of the crate:

[tex]a=\frac{F}{m}=\frac{60 N}{160 kg}=0.375 m/s^2[/tex]

2. Distance: 3 m

For this problem we can use the following SUVAT equation:

[tex]S=ut+\frac{1}{2}at^2[/tex]

where

S is the distance travelled by the crate

u = 0 is the initial velocity, since it starts from rest

t = 4 s is the time elapsed

[tex]a=0.375 m/s^2[/tex] is the acceleration

Substituting all numbers into the equation,

[tex]S=0+\frac{1}{2}(0.375)(4)^2=3 m[/tex]

3. Work done: 180 J

The work done by a force, assuming that the force is parallel to the displacement of the object, is given by

W = F d

where

W is the work done

F is the magnitude of the force

d is the displacement

Here we have

F = 60 N

d = 3 m

So the work done is

[tex]W=(60 N)(3 m)=180 J[/tex]

4. Final velocity: 1.5 m/s

The final velocity of the crate can be found by using the following SUVAT equation:

[tex]v^2 = u^2 +2ad[/tex]

where here

u = 0 is the initial velocity

[tex]a=0.375 m/s^2[/tex] is the acceleration

d = 3 m is the distance covered

Substituting all the numbers that we have, we found:

[tex]v=\sqrt{u^2 +2ad}=\sqrt{0^2+2(0.375)(3)}=1.5 m/s[/tex]

5. Kinetic energy: 180 J

The kinetic energy of an object is given by

[tex]K=\frac{1}{2}mv^2[/tex]

where

m is the mass of the object

v is the velocity

Here we have

m = 160 kg is the mass of the crate

v = 1.5 m/s is its final velocity

So the kinetic energy of the crate is

[tex]K=\frac{1}{2}(160)(1.5)^2=180 J[/tex]

Answer: 14.7kJ, 29.4kJ, 44.1kJ

Explanation:

The gravitational potential energy is the energy that a body or object possesses, due to its position in a gravitational field.  

In the case of the Earth, in which the gravitational field is considered constant, the value of the gravitational potential energy [tex]U_{p}[/tex] will be:  

[tex]U_{p}=mgh[/tex]  

Where [tex]m[/tex] is the mass of the object, [tex]g=9.8m/s^{2}[/tex] the acceleration due gravity and [tex]h=500m[/tex] the height of the object.  

Knowing this, let's begin with the calculaations:

For m=3kg

[tex]U_{p}=(3kg)(9.8m/s^{2})(500m)[/tex]  

[tex]U_{p}=14700J=14.7kJ[/tex]  

For m=6kg

[tex]U_{p}=(6kg)(9.8m/s^{2})(500m)[/tex]  

[tex]U_{p}=29400J=29.4kJ[/tex]  

For m=9kg

[tex]U_{p}=(9kg)(9.8m/s^{2})(500m)[/tex]  

[tex]U_{p}=44100J=44.1kJ[/tex]  

Answer:

im note too sure

Explanation:

please ask again later

Answer: 2Ω

Explanation:

V = IR

R = V/I

R = 10/5 = 2Ω

Hope it helped!

Answer:

52.9 N, 364.7 N

Explanation:

First of all, we need to resolve both forces along the x- and y- direction. We have:

- Force A (178 N)

[tex]A_x = (178 N)(cos 41.7^{\circ})=132.9 N\\A_y = (178 N)(sin 41.7^{\circ})=118.4 N[/tex]

- Force B (259 N)

[tex]B_x = (259 N)(cos 108^{\circ})=-80.0 N\\B_y = (259 N)(sin 108^{\circ})=246.3 N[/tex]

So the x- and y- component of the total force acting on the block are:

[tex]R_x = A_x + B_x = 132.9 N - 80.0 N =52.9 N\\R_y = A_y + B_y = 118.4 N +246.3 N = 364.7 N[/tex]

Answer:

x: 52.9

y: 364.7

Explanation:

Answer:

v² = u² + 2x²

Explanation:

v² = u² + 2as​ is only valid for constant acceleration.  Here, the acceleration is a function of position.  We can find the function of velocity by integrating.  Acceleration is the derivative of velocity with respect to time:

a = 2x

dv/dt = 2x

Apply chain rule:

dv/dt = dx/dt × dv/dx

dv/dt = v × dv/dx

Therefore:

v dv/dx = 2x

Separate the variables and integrate:

v dv = 2x dx

½ v² |ᵤᵛ = x² |₀ˣ

½ (v² − u²) = x²

v² − u² = 2x²

v² = u² + 2x²

The safety contract will include basic lab safety guidelines such as:

Further Explanation:

In his safety contract, Chris will find statements that has him agreeing that he will behave appropriately inside the lab especially since they will be working with an open fire (Bunsen burner) or a heating equipment (hot plate) to change the temperature of the water. Proper behavior and basic expectation inside a lab are in the items listed above.

Learn More

Keywords: lab safety, lab contract

Answer:

th

Explanation:

The following formula relates applied force to pressure:

P = F/A

P is the pressure, F is the applied force, and A is the area over which the force is applied.

Unfortunately we cannot calculate the pressure if we don't know the area of contact between the ball and the tube.

Answer:

10 kW

Explanation:

First convert km/hr to m/s.

72 km/hr × (1000 m / km) × (1 hr / 3600 s) = 20 m/s

The power is:

P = Fv

P = (500 N) (20 m/s)

P = 10000 W

P = 10 kW

The power applied by the bike is 10 kW.

The power applied by the bike climbing the inclined road at a constant speed with a force of 500 N is calculated as 10000 watts or 10 kW using the formula Power = Force x Velocity.

The problem at hand involves calculating the power applied by a bike when it ascends an inclined road at a uniform speed while applying a force. To find the power, we need to use the formula for power in the context of mechanical systems, which is Power (P) = Force (F) × Velocity (v). Here, force is given as 500 N and the velocity can be converted from 72 km/hr to meters per second (m/s) by multiplying it with (1000 m/km) / (3600 s/hr), which gives us 20 m/s.

Therefore, the power applied by the bike is P = 500 N × 20 m/s = 10000 watts or 10 kW.

This is the instantaneous power delivered by the force that the bike exerts on the road to overcome resistant forces like friction and air resistance while moving uphill. It's important to note that the power can change if any of the variables, such as speed or the force, change.

Answer:

A) Decomposing water requires high activation energy

Explanation:

The sun is a renewable resource, because the solar energy we use is less than the solar energy being created.  Decomposing water produces hydrogen gas and oxygen gas, which aren't toxic.  The oxygen is used in the combustion of the hydrogen gas.  However, splitting water molecules into hydrogen and oxygen takes a lot of energy.

Answer:

A Decomposing water requires high activation energy

Explanation:

Explanation:

Power = work / time

Work = force × distance

Therefore:

Power = force × distance / time

Since the distance is the same, he would have to either increase the force he exerts or decrease the time (increase his velocity) in order to increase the amount of work done.

Answer:

The correct answer is B) The player would need to use a greater force and take less time.

Explanation:

hope this helps :)

can i get brainliest plz

Answer:

D. They diverge from the focal point.

Explanation:

Incoming light rays diverge from the focal point is they are parallel to the principal axis of a convex lens.

Answer:

They diverge from the focal point.

Explanation:

A convex lens is also called as converging lens. If the rays of light are parallel to the principal axis of a convex lens, it passes through the focal point of the lens.

For a converging lens, the ray of light diverge from the focal point of the lens. The image formed by a convex lens is real and inverted. When the object is placed between the focus and the optical center, the image is virtual and erect.

So, the correct option is (d) "They diverge from the focal point".

Answer:

The plan would result in domination of the country by special interests. - C.

Explanation:

critacal temperature

Answer: tuba- alloy

paper-polymer

pot- ceramic

Explanation:

Answer:

Tuba -  Alloy

Paper -  Polymer

Pot - ​Ceramics

Explanation:

Alloy : An alloy is a substance which made up of two more than two types of metal.It is uniform solid substance. For example : brass, steel etc

Ceramics: Articles , figures made up of clay which are hardened by the action of heating. For example : pots, crockery etc.

Polymer: These are the substance composed repeating units of of same chemical units which held together by covalent bonds.The single chemical unit is known as monomer. For example : plastic , rubber etc.

Tuba is an musical instrument similar made up of brass. And brass is an alloy of copper and zinc. Hence, an alloy.

Paper is majorly made up of wood pulp.And Wood pulp consists cellulose which is a polymer of glucose molecule.Hence, polymer.

Pot is made up of clay and heated to hardened them.Hence, ceramics.

Answer:

Space Probe

Explanation:

It is actually a type of satellite to explore space considering the useful dimensions for discoveries and observations that are useful for existence of life. It collects data and returns back to the base with records that are purpose of flight.

The Voyager is a designed robotic spacecraft as a part of space technology to explore space and sends data to Earth.

Explanation:

The voyager has been designed as an integral part of the space program known as the VOYAGER, which explores space. This program has been launched into the space by the NASA.

The satellite has been communicating and sending various space informational data to the space information base positioned in NASA known by the name of DEEP SPACE NETWORK. This program was launched in the year of 1977.

Earth is considered an inner planet because it lies between the Sun and the main asteroid belt, along with the other terrestrial planets Mercury, Venus, and Mars.

Earth is considered to be an inner planet because it is located between the sun and the main asteroid belt. This asteroid belt is the region of the solar system between the orbits of Mars and Jupiter, where most asteroids are found. Earth, along with Mercury, Venus, and Mars, falls into the category of terrestrial or inner planets, which are closer to the Sun and primarily composed of rock and metal with solid surfaces that have geological features.

Correct answer to the student's question: B- It is located between the sun and the main asteroid belt.

Answer:

104 N

Explanation:

Calculate the spring stiffness:

F = kx

32.5 N = k (0.500 cm)

k = 65 N/cm

Find the force for the new length:

F = kx

F = (65 N/cm) (1.60 cm)

F = 104 N

Answer:

120°

Explanation:

Draw a free body diagram.  There are three forces acting on the traffic light.  Two tension forces acting along the cables, and weight.

The tension forces have an angle θ between them.  That means each tension force forms an angle of θ/2 with respect to the vertical.  So the y component of each tension force is:

Ty = T cos (θ/2)

Sum of the forces in the y direction:

∑F = ma

Ty + Ty − W = 0

2 Ty = W

Substituting:

2 T cos (θ/2) = W

If W = T, then:

2 W cos (θ/2) = W

2 cos (θ/2) = 1

cos (θ/2) = 1/2

θ/2 = 60°

θ = 120°

The angle between the cables Ф so that the tension in each cable will be equal to the weight of the traffic signal light is 120°

Let

Now, the angle between the tension and the vertical is α = Ф/2.

The net force vertical force on the traffic light is F = Tcosα + T'cosα - W

Since the traffic light is in equilibrium, we have that F = 0

So, F = Tcosα + T'cosα - W

Tcosα + T'cosα - W = 0

Tcosα + T'cosα = W

Now, since the tension in each cable equals the weight of the traffic light, T = T' = W.

So, Tcosα + T'cosα = W

Wcosα + Wcosα = W

2Wcosα = W

cosα = W/2W

cosα = 1/2

α = cos⁻¹(1/2)

α = 60°

Since α = Ф/2

Ф = 2α

Ф = 2(60°)

Ф = 120°

So, the angle between the cables Ф so that the tension in each cable will be equal to the weight of the traffic signal light is 120°

Learn more about angle between cables here:

https://brainly.com/question/16604722

Answer:

When the neutral point of a magnet is broken into two each part gains polarity opposite to each other. This is because the broken parts of this magnet become a complete magnet as the Original magnet with complete poles N and S.  

When the neutral region of a bar magnet is broken into two, the broken two parts of the magnet becomes a whole magnet in itself, that is from one magnet, two new magnets are formed.

Explanation:

The neutral region exists in the mid of the magnet as the magnet is only polarized at the end on whole. Thereby the broken pieces on its ends acquires the polarity on the two end sides.

This occurs in both the broken parts. With the acquirement of the polarity, one side becomes the North Pole and the other side becomes the South pole. Therefore, the broken bar magnets becomes a magnet in itself.  

Answer:

Unlike heirloom seeds, if one saves a hybrid seed, one will not get the same plant again.

Explanation:

The statement that can be removed without affecting the reliability of overall paragraph is, "unlike heirloom seeds, if one saves a hybrid seed, one will not get the same plant again". This is because even if we remove this line, the paragraph still looks completely understandable, reliable and in a flow.

If we talk about hybrid plants, we know that they are produced through cross pollination of the crops with desired traits. Although they are sterile and cannot produce offspring, however the plants which are raised from these seeds are edible and quite healthy. This is why these plants have better yield and a better resistance against environmental constraints like diseases and stresses. After the production, hybrid seeds are stored and they are able to produce plants of similar types.

Hope it helps!

Answer:

C on edg

Explanation:

Answer:

2 m

Explanation:

Work = force × distance

500 J = 250 N × d

d = 2 m

She moved the couch 2 meters.

Answer:

5.61 seconds

Explanation:

Given:

y₀ = 0 m

y = 14.0 m

v₀ = 30.0 m/s

a = -9.8 m/s²

Find: t

y = y₀ + v₀ t + ½ at²

14 = 0 + 30t − 4.9t²

4.9t² − 30t + 14 = 0

Solve with quadratic formula:

t = [ -b ± √(b² − 4ac) ] / 2a

t = [ 30 ± √(900 − 274.4) ] / 9.8

t = 0.509, 5.61

t = 0.509 is the time when the ball first reaches the height of 14.0 meters on the way up.  t = 5.61 is the time when the ball reaches the height of 14.0 meters on the way down.

Since we know the ball reaches its maximum height and begins falling again, we want the second time.  t = 5.61 seconds.

Answer:

7500 m/s

Explanation:

Centripetal acceleration = gravity

v² / r = GM / r²

v = √(GM / r)

Given:

G = 6.67×10⁻¹¹ m³/kg/s²

M = 5.98×10²⁴ kg

r = 6.8×10⁵ + 6.357×10⁶ = 7.037×10⁶ m

v = √(6.67×10⁻¹¹ (5.98×10²⁴) / (7.037×10⁶))

v = 7500

The orbital velocity is 7500 m/s.

The orbital velocity is 7500 m/s.

Orbital velocity is defined as the minimum velocity a body must maintain to stay in orbit.

Given

h = 6.8 E 5 m = 6.8 * [tex]10^{5}[/tex] m

mass of satellite = 5.6 * [tex]10^{5}[/tex] kg

Earth's mass : m(e)  = 5.98 E 24 kg

Earth's radius ; R(e) = 6.357 E 6 m

orbital velocity :v(orbiting ) = [tex]\sqrt{Gm(e) / R(e) + h}[/tex]

R(e) + h  = 6.8×10⁵ + 6.357×10⁶ = 7.037×10⁶ m

v = √(6.67×10⁻¹¹ * (5.98×10²⁴)) / (7.037×10⁶))

v = 7500 m/s

The orbital velocity is 7500 m/s.

learn more about orbital velocity

https://brainly.com/question/16040381?referrer=searchResults

#SPJ2

Answer:

Synthetic Materials are man-made; natural materials are only warmer than synthetic materials, if the natural material is obtained from an animal. Wool is warmer than any synthetic material available, but polyester (a synthetic material) can be warmer than cotton (a natural plant-based material).

Explanation:

The gravitational potential energy is the energy that a body or object possesses, due to its position in a gravitational field.

That is why this energy depends on the relative height of an object with respect to some point of reference and associated with the gravitational force.

In the case of the Earth, in which  the gravitational field is considered constant, the value of the gravitational potential energy [tex]U_{p}[/tex] will be:

[tex]U_{p}=mgh[/tex]  

Where [tex]m[/tex] is the mass of the object, [tex]g[/tex] the acceleration due gravity and [tex]h[/tex] the height of the object.

As we can see, the value of [tex]U_{p}[/tex] is directly proportional to the height.

Answer:

4020 N

Explanation:

First convert km/h to m/s.

54.0 km/h × (1000 m / km) × (1 h / 3600 s) = 15.0 m/s

Sum of the forces in the radial direction:

∑F = ma

F = m v² / r

F = (1250 kg) (15.0 m/s)² / 70.0 m

F ≈ 4020 N