1. Review Problem #1
A hockey puck is shot across the ice with an initial speed of 15 m/s. It travels 40 m before coming to rest. What is the coefficient of friction between the puck and the ice?

2. Review Problem #2
A 20 kg child sits in a 40 kg wagon and is pulled down the sidewalk by his brother. The coefficient of friction between the wheels and the ground is What minimum force must the brother use to pull the wagon? If he used 100 N, what acceleration will the wagon have?

3. Tension Tension is a pulling for in a rope, wire, cable, etc.
Tension forces are equal in all parts of the rope.
Tension can act in any direction, but it is always a pull, never a push.

4. Tension Example
Determine the tension in the rope for the diagram below.
10 kg

5. Tension Example #2
Find the acceleration and tension of the system below…
5 kg
1 kg

6. Tension Example #3
Find the acceleration and tension of the system below…
5 kg
10 kg

7. Tension Example 4
Find the acceleration and tension of the system below. The coefficient of friction between the box and the table is 0.3.