Mass of ball, m=300g=0.3‌kg height, h=10m. If v be the speed of ball when it reaches the ground, then ‌v2=u2+2gh=0+.2×10×10 ‌⇒‌‌v=200⇒v=10√2m∕s ‌ For sandy ground, initial velocity of ball, v=10√2m∕s Final velocity v′=0 distance travelled by the ball in sand, s=1.5m if a′ be retardation applied on the ball in sandy ground, then using equation v′2=v2−2as 0=(10√2)2−2a×1.5⇒a=‌
200
3
m∕s2 ∵ Average resistance offered by the sand F=m⋅a=0.3×‌