E. Reach each item carefully. Underline the letter of the correct answer.
1.The janitor has just finished mopping the floor. He left a sign that says, ”Wet floor”. Why did he leave this warning?
A. He does not want the floor to get dirty
B. He wants to warn the people of the risk of accident due to lessened static friction on the floor.
C. He wants to warn people of the risk of accident due to kinetic friction on the floor.
D. He does not want his work interrupted.

2. Which of the following does NOT reduce friction?
A. grease B. oil C. sand D. water

3. Which of the following does not overcome frictional forces?
A. Applying lubricants C. using rollers
B. Increasing perpendicular forces D. creating streamlined structures

4. Which of the following situations show a positive effect of friction?
A. slippery floor C. pushing heavy furniture
B. worn out tires D. firm grip of tennis rackets

5. Which of the following is NOT true about Friction?
A. Friction always produce undesirable effects.
B. Friction acts in the opposite direction of motion.
C. Friction increases when one object is on top of the other.
D. Greater work is done in pushing objects because of Friction.

6. A swimmer uses a cap when swimming in order to______
A. Avoid formation split ends
B. Reduce friction between hair and water.
C. Increase friction between head and water.
D. Protect the hair from effects of chlorine.

7. Which of the following has a greatest friction?
A. polished floor C. wet floor
B. sandy floor D. tiled floor

8. Which of the following statements best describes Friction?
A. it is a force that occurs between solids.
B. It is a force that occurs only on rough surfaces.
C. It is a force that occurs between solids and liquids.
D. It is a force that occurs when surfaces touch each other.

9. How can you best reduce friction between the bottom or feet of furniture and the floor?
A. By smoothing the floor
B. By keeping furniture on their place
C. By applying lubricants like wax on the floor
D. By putting wheels on rollers on the bottom or feet of furniture
10. Which of the following shows that friction is undesirable?
A. pushing furniture C. using the breaks when approaching a stoplight
B. lightning a matchstick D. walking on wet floor
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E. Reach each item carefully. Underline the letter of the correct answer.
1.The janitor has just finished mopping the floor. He left a sign that says, ”Wet floor”. Why did he leave this warning?
A. He does not want the floor to get dirty
B. He wants to warn the people of the risk of accident due to lessened static friction on the floor.
C. He wants to warn people of the risk of accident due to kinetic friction on the floor.
D. He does not want his work interrupted.

2. Which of the following does NOT reduce friction?
A. grease B. oil C. sand D. water

3. Which of the following does not overcome frictional forces?
A. Applying lubricants C. using rollers
B. Increasing perpendicular forces D. creating streamlined structures

4. Which of the following situations show a positive effect of friction?
A. slippery floor C. pushing heavy furniture
B. worn out tires D. firm grip of tennis rackets

5. Which of the following is NOT true about Friction?
A. Friction always produce undesirable effects.
B. Friction acts in the opposite direction of motion.
C. Friction increases when one object is on top of the other.
D. Greater work is done in pushing objects because of Friction.

6. A swimmer uses a cap when swimming in order to______
A. Avoid formation split ends
B. Reduce friction between hair and water.
C. Increase friction between head and water.
D. Protect the hair from effects of chlorine.

7. Which of the following has a greatest friction?
A. polished floor C. wet floor
B. sandy floor D. tiled floor

8. Which of the following statements best describes Friction?
A. it is a force that occurs between solids.
B. It is a force that occurs only on rough surfaces.
C. It is a force that occurs between solids and liquids.
D. It is a force that occurs when surfaces touch each other.

9. How can you best reduce friction between the bottom or feet of furniture and the floor?
A. By smoothing the floor
B. By keeping furniture on their place
C. By applying lubricants like wax on the floor
D. By putting wheels on rollers on the bottom or feet of furniture
10. Which of the following shows that friction is undesirable?
A. pushing furniture C. using the breaks when approaching a stoplight
B. lightning a matchstick D. walking on wet floor