Mini-Quiz: Bearings Reduce Friction

1. When are roller bearings used instead of ball bearings?

   When the the friction must be increased for moving an objectSorry, not correct. Try another button. When the load is too heavy for ball bearingsThat is correct. You know about bearings. Whenever an axle is not requiredGood try, but not right. Select another answer.

2. Why is the friction less with ball bearings?

   The friction is actually greater than with roller bearingsOops! Wrong answer. Re-read the question and try again. Only two ball bearings are neededSorry, not correct. Try another button. The point of contact is very smallCorrect. Now you are rolling!

3. What is the mechanical advantage when using bearings?

   The sliding coefficient of friction divided by the rolling coefficientThat is correct. You know about bearings. There is no mechanical advantage in using bearingsGood try, but not right. Select another answer. The rolling coefficient of friction divided by the sliding coefficientOops! Wrong answer. Re-read the question and try again.

Pick an answer to see instant feedback. Re-read the lesson if you miss one.