Question

A motorcycle and a bus are moving
with same momentum. Which of them has
greater kinetic energy? Justify

Answer 1

Dear Student,

Let mass of Bus =M

mass of Motorcycle=m

velocity of Bus =v

velocity of Motorcycle =V

we know M>m.

Given Same Momentum i.e. Mv=mV

M/m=V/v

V>v

velocity of Motorcycle > velocity of Bus

now kinetic energy is given by mv²/2

k.E for Bus =Mv²/2=Mv.v/2 ...............(1)

k.E for Motorcycle =mV²/2=mV.V/2 ................(2)

from eqn (1) and (2) we can see that

we know

Mv=mV

so just have to compare

V/2 and v/2

we also know V>v

so V/2>v/2

from this we can conclude that

k.E for Motorcycle >k.E for Bus

Regards