Friction

1. What is force of friction?
2. In which direction does the force of friction acts?
3. Alisha runs her toy car on a dry marble floor,wet marble floor, newspaper and towel spread on the floor.Arrange the force of friction acting on the car on different surfaces in increasing order.
4. Suppose you tilt your study table and notebooks kept on it start falling.Write the direction of frictional force acting on it.
5. You spill a bucket of soapy water on a marble floor accidentally.Would it make it easier or more difficult for you to walk on the floor? Why?
6. If two students has to push one box each on similar floor.One of the box is heavier compared to other. Who will have to apply a larger force,the one carrying the lighter box or the other carrying the heavier box and why?
7. Is friction contact or non contact force?

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