Question

the kinetic energy of an object with mass m moving with a velocity of 5 m/s is 25 j what will be its kinetic energy when its velocity is doubled what will its kinetic energy when it is velocity increased 3 time

Answer 1

100 J, 225 J

Step-by-step explanation:

The kinetic energy of an object is given by:

`K=(1)/(2)mv^2`

where

m is the mass of the object

v is the velocity of the object

In this problem, the initial kinetic energy of the object is

K = 25 J

Then, the velocity is doubled, which means

v' = 2v

Therefore, the new kinetic energy will be

`K'=(1)/(2)m(2v)^2 = 4((1)/(2)mv^2)=4K`

Therefore, the kinetic energy has quadrupled:

`K' = 4(25)=100 J`

Later, the velocity is tripled, which means

v'' = 3v

Therefore, the new kinetic energy will be

`K''=(1)/(2)m(3v)^2 = 9((1)/(2)mv^2)=9K`

Therefore, the kinetic energy has increased by a factor of 9:

`K' = 9(25)=225 J`