Question

If the person and the cricket ball consist of a system, find the position and velocity of the center of mass of the system at time t=0.5 s

Answer 1

The position of the center of mass after 0.5s can be calculated using the 2nd equation of motion.

$y=y_0+v_yt+\frac{1}{2}gt^2$

$v_y=0$

g=9.8m/s

$y_0=11.5m$

t=0.5

$y=11.5+\frac{1}{2}×(-9.8)×0.5^2=10.275m$

Velocity of the center of mass after 0.5sec is calculated using the 1st equation of motion:

$v_y=u_y+at$

$u_g=0$

$v_y=-9.8×0.5= -4.9ms^{-1}$

The negative sign signifies that the directions of motion