Question

Two particles $1$ and $2$ are thrown in the directions shown in figure simultaneously with velocities $5m/s$ and $20m/s$. Initially, particle $1$ is at height $20m$ from the ground. Taking upwards as the positive direction, find the acceleration of $1$ with respect to $2$

Answer 1

Given : $u_1=-5m/s$ $u_2=20m/s$

Acceleration of 1 $a_1=-g$

Acceleration of 2 $a_2=-g$

Acceleration of 1 w.r.t 2 $a_{12}=-g-(-g)=0$