A solid sphere of mass I kg, radius 10 cm rolls down an inclined plane of height 7 m. The velocity of its centre as it reaches the ground level is

Options

A. 7 m/s
B. 10 m/s
C. 15 m/s
D. 20 m/s

Answer

B

Explanation

`v = sqrt(1 + ((2gh)/(k^2))/(R^(2)))`
For a solid sphere , `(k^2)/(R^2) = (2)/(5) , v = sqrt((2 xx 10 xx 7)/((1 + (2)/(5)))) = 10 ` m/s