Blocks A and B of masses 5 kg and 10kg are placed as shown in figure. If block A is pulled with 50 N. Find out acceleration of the A and B. if coefficient of friction between A and B is 0.5and between B and ground is 0.4.

Explanation

Limiting friction between A and B, `f_(1)=mu_(1)R_(1)=0.5xx5g=24.5N`
Limiting friction between B and ground `f_(2)=mu_(2)R_(2)=0.4xx15g=58.8N`
For block `A 50-f_(1)=5xxarArr50-24.5=5xxarArra=5.1 m//s^(2)`
For block B accelerating force `f_(1)=24.5N` is less than limiting friction `f_(2)=58.8N` so block B will remain at rest.