After the box comes to rest at position x1, a person starts pushing the box, giving it a speed v1. When the box reaches position x2 (where x2>x1), how much work Wp has the person done on the box

0.5m(v1)²

Explanation:

We know that work done on an object is equal to the change in the kinetic energy of that object. Hence,

W. D = ΔK. E.

ΔK. E. = K. E.(final) - K. E.(initial)

Initial Kinetic energy, K. E.(initial), is:

K. E.(initial) = 0 (the box was at West)

Final K. E., K. E.(final) is:

K. E.(final) = 0.5*m*(v1)²

Hence, work done on the box will be:

W. D. = 0.5m(v1)² - 0

W. D. = 0.5m(v1)²

c)as speed changes, wavelength and frequency change.

everything changes!