Worksheet 2 Friction


Worksheet 2

Friction 

A. Fill in the Blanks

  1. Friction always acts in the __________ direction to motion.
  2. The force of friction is greater between __________ surfaces.
  3. The irregularities on surfaces cause __________.
  4. __________ are used to reduce friction in machines.
  5. A __________ balance measures the force of friction.


B. Conceptual Questions

  1. Why does a rolling object experience less friction than a sliding object?
  2. Why are shoes designed with grooves or tread patterns on their soles?
  3. What is the role of spring balance in studying friction?


C. Think & Apply 

  1. A wooden block is pulled on a rough table and then on a smooth table. Predict and explain the difference in friction.
  2. Why do ball bearings reduce friction in machines?
  3. If friction didn’t exist, what challenges would we face in daily life? Think of at least three situations.


D. Advantages and Disadvantages 

  1. List two situations where friction is helpful and two where it is not useful.
  2. Suggest two ways to reduce unwanted friction and two ways to increase useful.


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