Two carts are involved in an elastic collision. Cart A with mass 0.550 kg is moving towards Cart B with mass 0.550 kg, which is initially at rest. Cart A stops after the collision and Cart B begins to move. A)If cart A has an initial velocity of 0.8 m/s , what is the velocity of Cart B after the collision?B)What is the initial kinetic energy of Cart A?C)What is the initial kinetic energy of Cart B?D)What is the final kinetic energy of Cart A?E)What is the final kinetic energy of Cart B?F)Is the kinetic energy conserved for elastic collisions?G)Is the momentum conserved for elastic collisions?

A) is the final velocity of the cart B after collision.

B)

C)

D)

E)

F) Yes, here the kinetic energy is conserved because the mass of both the bodies involved in the collision is same.

G) Yes, momentum is always conserved for an elastic collision.

Explanation:

Given:

A)

As given in the question that the cars undergo an elastic collision:

According to the conservation of momentum:

is the final velocity of the cart B after collision.

B)

Initial kinetic energy of cart A:

C)

Initial kinetic energy of cart A:

D)

The final kinetic energy of cart A:

E)

The final kinetic energy of cart B:

F)

Yes, here the kinetic energy is conserved because the mass of both the bodies involved in the collision is same.

G)

Yes, momentum is always conserved for an elastic collision.

b.transmitters send radio waves, and receivers capture radio waves.

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.