Provide at least three reasons why friction is needed.

Sample Response: Friction allows people and objects to move. It provides traction for an object to start moving or change direction. It can also give people a better grip on objects. Finally, friction keeps objects in place when they are set down.

-Friction makes movement possible.

-Friction provides traction

-Friction makes it easier to hold on to objects

-Friction keeps objects in place.

measure their densities same density, same sub

b. false

explanation:

suppose a rock in free fall is dropped off a cliff. after falling for 5 seconds, its speed would not be 100 m/s.