Normal Force in an Elevator

Do now

When traveling up and down on an elevator, name two moments in which a person is:

• Accelerating upwards.

• Accelerating downwards.

• Not accelerating.

Announcements

• Question 11 will be regraded (calculus argument)

• Any voting done by midnight will count toward this marking period and then it will be restarted on Sunday and close by 11/19. For example, if you got the maximum votes (10 points), that will go toward yesterdays exam and then you will start from zero on Sunday.

Agenda

• 3 Most missed questions

• Problem set (15-18 minutes)

• Study technique for any advanced physics or mathematics class

Question 11 (True)

If an object is at rest, then the velocity-time graph will be a line with zero slope.

What you’re thinking

•If there is a zero slope on a velocity time graph, then the object is at rest.

Question 11 (True False)

If an object is at rest, then the velocity-time graph will be a line with zero slope.

Question 14 (False)

An object which is slowing down is represented by a line on a velocity-time graph which is moving in the downward direction.

Question 38 (True)

As a projectile rises towards the peak of its trajectory, the vertical velocity will decrease; as it falls from the peak of its trajectory, its vertical velocity will decrease.

Normal Force Practice Set (15 minutes)