A uniform sphere of mass m and radius R is placed on a rough horizontal surface (Fig). The sphere is struck horizontally at a height h from the floor. Match the following:

(a) h = R/2 (i) Sphere rolls without slipping with a constant velocity and no loss of energy.

(b) h = R (ii) Sphere spins clockwise, loses energy by friction.

(c) h = 3R/2 (iii) Sphere spins anti-clockwise, loses energy by friction.

(d) h = 7R/5 (iv) Sphere has only a translational motion, looses energy by friction.

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Payal Gupta | Contributor-Level 10

9 months ago

This is a short answer type question as classified in NCERT Exemplar

Consider a fig in which m is mass of sphere and R is the radius having h height above the floor

The sphere will roll without slipping when w=v/r where v is linear velocity and w is angular velocity .

By conservation of momentum

mv (h-R

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