Question

A solid sphere of mass 1 kg and radius 10 cm rolls without slipping on a horizontal surface, with velocity of 10 emfs. The total kinetic energy of sphere is ______.

Options

• 0.007 J

• 0.05 J

• 0.01 J

• 0.07 J

Answer 1

A solid sphere of mass 1 kg and radius 10 cm rolls without slipping on a horizontal surface, with velocity of 10 emfs. The total kinetic energy of sphere is 0.007 J.

Explanation:

KE = `1/2 "I"omega^2 + 1/2 "mv"^2`

`= 1/2 (2/5 "MR"^2) "v"^2/"R"^2 + 1/2 "Mv"^2`

`= 1/5 "Mv"^2 + 1/2 "Mv"^2`

`= 7/10 "Mv"^2`

`= 7/10 xx 1 xx 10 xx 10^-2`

= 7 × 10^-2 J

= 0.007 J