Q5.34 Two bodies A and B of masses 5 kg and 10 kg in contact with each other rest on a table against a rigid wall (Fig. 5.21). The coefficient of friction between the bodies and the table is 0.15. A force of 200 N is applied horizontally to A. What are (b) the action-reaction forces between A and B ? What happens when the wall is removed? Does the answer to (b) change, when the bodies are in motion? Ignore the difference between and .
Consider block A.
The frictional force on block A will be :
or
Thus net force on B due to block A is = 200 - 7.5 = 192.5 N.
The net force on the partition is 177.5 N.
Using Newton's law of motion we have,
or
For block A :
or
So the required normal force is = 192.15 - 59.15 = 133.35 N.