Question

An a-particle and a proton is projected towards the same nucleus, in different experiments.

The ratio of their distances of closest approach is :

(A) 2 : 1, if their initial kinetic energy was same

(B) 8 : 1, if their initial momentum was same

(C) 1 : 2, if their initial speed was same

(D) 1 : 1, if their initial kinetic energy was same​

Answer 1

Answer:

m

∝

=4 amu mp=1 amu

K.ϵ

∝

K.ϵ

∝

.

=

1/2m

p

V

p

2

1/2m

∝

V

∝

2

=1

⇒4v

∝

2

=Vp

2

⇒Vp=2V

∝

we know that,

V

2

=u

2

+2aS

V

p

2

−up

2

=2aSp

V

∝

2

−u

∝

2

=2aS

∝

Initial velocities up=u

∝

=0

u

V

∝

2

V

p

2

=

S

∝

S

P

⇒Sp:S

∝

=4:1