1. Forces and Friction Problem Created for CVCA Physics By Dick Heckathorn 14 November 2K+3

2. A 25.0 kg block has been sliding on a frictionless, horizontal ice surface at 2.00 m/s. Suddenly it encounters a large rough patch where the coefficient of kinetic friction is -0.05. How far does the block travel on this rough surface? All questions refer to the motion on the rough surface.

3. Fice on b Ffriction Fe on b 1. How many different forces are acting on the block? Ignore air resistance. 5 4 0 2 3 1

4. Fe on b 2. What is the direction of the weight force? F E A C D B

5. Fice on b 3. What is the direction of the normal force? F E A C D B

6. Ffriction 4. What is the direction of the frictional force? F E A C D B

7. Fice on b Ffriction Fe on b 5. Is the block accelerating? Yes Not enough information No

8. Fice on b Fe on b 6. What is the acceleration in the y-direction? >0 Not enough information <0 =0

9. Ffriction 7. What is the acceleration in the x-direction? >0 Not enough information <0 + value in a ‘-’ direction =0

10. Fice on b Choices Ffriction +245 N -12.25 N +12.25 N -245 N (ma)x 0 N Fe on b y-direction x-direction ______ ______ -245 N 0 Weight Force ______ ______ Normal Force +245 N 0 ______ ______ Friction Force -12.25 N 0 ______ ______ (max) -12.25 N Total Force 0

11. Fice on b 9. Find the x-component of the acceleration, and use it to determine the acceleration. Ffriction Fe on b acceleration distance __________ __________ - 0.49 m/s2 4.08 m

12. That’s all folks!