Suppose a moving object has kinetic energy and then comes to rest. What describes the change in its kinetic energy?

A. It would remain constant.
B. It would double.
C. It would decrease by half.
D. It would become zero.

D

Explanation: The kinetic energy would become Zero.

According to conservative of energy, the total energy is equal to maximum K.E plus maximum P.E.

As the object comes to rest the potential energy will be maximum, and Kinetic energy becomes zero.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

find the sum of the two horizontal vectors and the sum of the two vertical vectors

isoceles right angled triangle