Question

asnwer this with full equations​

Answer 1

Answer:

Explanation:

Given that both bodies have equal momentum.

Let their momentum = P

We know kinetic energy = p²/2m

                              where p is the momentum and m is the mass of the body

Mass of first body, m₁ = 1 x 10³ = 1000kg

Mass of second body, m₂ = 4 x 10³ = 4000 kg

Ratio of their kinetic energies =

P²/ 2 x m₁   :  P²/ 2 x m₂  (as P²/2 is common, we cancel them out)

1/m₁ : 1/m₂  (cross multiplication)

m₂ : m₁

4000  :  1000

4 : 1

Hence the answer is option (b) 4:1

If u r wondering how I got kinetic energy = p²/2m here is how I got it:

We know kinetic energy = 1/2 x mv²

We know momentum (p) = mv

So in the place of mv² I take it as p² which is equal to m²v²

Since there is an extra m multiplied we also divide it with m hence getting p²/2m.

Hope it helps you :)