Question

A marble is allowed to roll down an inclined plane from a fixed height. At the foot of the inclined plane, it moves on a horizontal surface. On which surface will the marble move the shortest distance. Give the reason for your answer.

• A. covered with silk cloth
• B. covered with a layer of sand
• C. covered with a glass sheet

Answer 1

The correct option is B

covered with a layer of sand

1. As the block of marble rolls down on the sand, it will cover the shortest distance.
2. Sand particles will exert more frictional force on the marble block.
3. Hence marble block will move the shortest distance on the layer of sand.
4. While the other two surfaces will exert a lesser friction force.
5. As in both the surfaces, the offered frictional force is far less than the force exerted by sand.

Thus, option B is the correct option.