A spherical ball of mass 20 kg is stationary at the top of the hill of height100 m . Itrollsdownsmooth surfaceto ground then climbup anotherhill of height40 mand finally rollsdownto a horizontal base at a height of 15 m abovethe ground . The maximum velocity attainedby a ball is ....... ( g = 9.8 m//s^(2))

A spherical ball of mass 20 kg is stationary at the top of the hill of

1.	A spherical ball of mass 20 kg is stationary at the top of the hill of height100 m . Itrollsdownsmooth surfaceto ground then climbup anotherhill of height40 mand finally rollsdownto a horizontal base at a height of 15 m abovethe ground . The maximum velocity attainedby a ball is ....... ( g = 9.8 m//s^(2))
Answer» `40 ms^(-1)` `40 . 8 ms^(-1)` `34.3 ms^(-1)` NONE of these Solution :`1/2 mv_(1)^(2) +mgh_(1)=1/2 mv_(2)^(2) +mgh_(2)` `:. Mgh_(1)-mgh_(2)=1/2mv_(2)^(2) -1/2mv_(1)^(2)` ` :. MG(h_(1) - h_(2)) = 1/2 mv_(2)^(2) "" [ :. v_(1) = 0 ] ` ` :. 20 XX 9.8 [100-15] = 1/2 xx2v xxv_(2)^(2)` ` :.(20 xx 9.8 xx85 xx2)/20 = v_(2)^(2)` ` :. 40.816 ms^(-1) = v_(2)` ` :. v_(2) = 40.8 ms^(-1)`