Im getting the answer as quarter times of initial energy in question in the image.. but answer given is thrice the initial energy. Give me solution to it.

Vaidehi
45 Points
4 years ago
let E1 be the initial energy and E2 be the final one.Initial momentum be P1 and final be P2.we know$P=h/\lambda$
therefore $(P1/P2)=\lambda 2/\lambda 1=0.5$
ie P2=2 P1
Also $E=(P^2)/2m$
$(E1/E2)=P1^2/P2^2$
$(E1/E2)=(1/4)$
E2=4E1
$Energy to be added=E2-E1=3E1$