Applied Mechanics and Graphic Statics
A hoop of radius 3 m weighs 100 kg. It rolls along a horizontal floor so that at its centre of mass has a speed of 200 mm/sec. The work required to stop the hoop is
The force of friction always acts in a direction opposite to that in which a body is moving
All of these
The magnitude of the kinetic friction bears a constant ratio to the normal reaction between two surfaces. The ratio being slightly less than that in the case of limiting friction
For moderate speeds the force of friction remains constant but decreases slightly with the increase of speed
EXAMIANS