Question

When the mass and speed of the body is doubled then kinetic energy becomes?

Answer 1

Let’s have some arbitrary kinetic energy, we’ll call it KE1KE1

KE=12mv2KE=12mv2

Which means.

KE1=12m1v12KE1=12m1v12

Now let’s have some other kinetic energy KE2KE2

KE2=12m2v22KE2=12m2v22

So let’s say that our second one is like our first one, but its mass m2m2 is double the mass of the first state m1m1 and that its speed v2v2 is double the speed of the first state v1v1. If we put that in math instead of words.

m2=2m1m2=2m1

v2=2v1v2=2v1

Make those substitutions.

KE2=12(2m1)(2v1)2=(8)(12m1v12)=8KE1KE2=12(2m1)(2v1)2=(8)(12m1v12)=8KE1

Tada. If you double mass and double velocity, you get eight times the kinetic energy, no matter what your