Answer:
The coefficient of dynamic friction is 0.025.
Explanation:
Given:
Initial speed after the push is 'v' as seen in the graph.
Final speed of the stone is 0 m/s as it comes to rest.
Total distance traveled is,
Total time taken is,
Time interval for deceleration is 3.5 to 17.5 s which is for 14 s.
Now, average speed of the stone is given as:
Now, we know that, average speed can also be expressed as:
Now, from the graph, the vertical height of the triangles is,
The deceleration is given as the slope of the line from time 3.5 s to 17.5 s.
Therefore, deceleration is:
Frictional force is the net force acting on the stone. Frictional force is given as:
Now, from Newton's second law, net force is equal to the product of mass and acceleration.
Therefore,
Plug in 0.244 for 'a' and 9.8 for 'g'. This gives,
Therefore, the coefficient of dynamic friction is 0.025.