1. Which shows that friction is undesirable?

a. Pushing Furniture.
b.Lighting matchstick
c. walking on wet floors.
d. using the breaks when approaching a spotlight

2.. Friction is a Force that constantly acts_____.

a. no movement at all
b. upright to the object's motion.
c. in the same wat as the object's motion.
d. contrasting to the object's normal motion

3. Which of the following surfaces has less friction?

a. cement.
b.grass.
c. rough floor.
d. tiled floor.

4. listed materials below can help reduce friction except_____.

a.ball bearings
b. oil.
c. sand.
d. wax.

5. listed materials below can help increase friction except_____.

a. rought surfaces.
b. rubber.
c. using lubricant
d. weight

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