A charged body is kept in an electric field where it experiences a constant acceleration of 10 m/s2 in the positive x-direction. The body hits wall after travelling 4 m and rebounds but can travel only upto 2 m before coming to rest momentarily . If the body was in contact with the wall for 12 ms then find the average acceleration of it due to the impact?
−1.26×103m/s2
Let's break the motion into 2 chunks
1. Forward Motion–––––––––––––––––––
u = 0 a=+10m/s2
v= v m/s
s = + 4m so v2=u2+2as
v=√80m/s
Backward Motion––––––––––––––––––––
Let Initial velocity = u v = 0
∴ ball is stopping
a = 10 m/s2
s = -2m since in negative x direction
v2−u2=2.10(−2)
u2=40
u=±√40m/s
We know u will be negative as particle after collision starts moving in negative direction.
So u=−√40m/s
So during collision period ball came with v=+√80m/s
after 12×10−3s
Ball rebounded back with v = −√40m/s
a=−√40−√8012×10−3
a=−1.2×103m/s2
Negative sign says that the particles average acceleration during collision was in negative x-direction.