Question

A ball thrown vertically upward reaches a maximum height of 30 find the with which it was thrown

Answer 1

it may be thrown with an object which weighs equal to it.

Answer 2

V²-U²= -2g×s

here s= 30 m

as at top V= o

then U²=2g s

then U²=2×10×30=600

then U= √6 ×10
then U=24.5 m/s approximately