6.1 - Vector diagram for UCM

Do now ( 5 mins)

2

1. Toby is running down the street at a velocity of +2.0 m/s

when he spots a squirrel. He accelerates to a velocity of
+5.5 m/s in 2.5 seconds in order to catch the squirrel.

a. At what rate did Toby accelerate?

vi

t

vf

Do now ( 5 mins)

3

1. Toby is running down the street at a velocity of +2.0 m/s

when he spots a squirrel. He accelerates to a velocity of
+5.5 m/s in 2.5 seconds in order to catch the squirrel.

b. How far did Toby travel while he was accelerating?

vi

t

vf

Do now ( 5 mins)

4

1. Toby is running down the street at a velocity of +2.0 m/s

when he spots a squirrel. He accelerates to a velocity of
+5.5 m/s in 2.5 seconds in order to catch the squirrel.

c. After accelerating, Toby remains at a constant
velocity of 5.5 m/s. How far will he travel after another
7 seconds passes?

vi

t

vf

Stamp

5

What are the thinking steps for selecting a kinematic
formula?

Launch 1

6

Launch 1

7

Demonstration

Launch 1

8

1. What about this demo reminds you

of the video of the ride?

2. How does this demo help us make

sense of the phenomena?

Launch 1

3. Draw a diagram to represent the motion
of your classmates spinning in the
demonstration.

First Attempt:

CFS:

❏ Draw a circle and include arrows to depict the direction of rotation/revolution.

❏ Include a solid line vector pointing to the direction of force.

❏ Include a dotted line vector to show the velocity of the object at each point.

10

Revised Model

11

Fc = Centripetal force
vector

ac = Centripetal
acceleration vector

v= tangential/ linear
velocity vector.

STAMP:
What needs to be labeled in a uniform circular
motion drawing?

12

1. The direction of rotation/revolution.
2. centripetal force ( the net force for UCM) .
3. Centripetal acceleration.
4. Tangential velocity.