Two blocks of masses 2 kg and 4kg are connected through a massless inextensible string. The co-efficient of fricition between 2kg block and ground is 0.4 and the coefficient of friction between 4kg block and ground is 0.6. The forces `F_(1)=10N` and `F_(2)=20N` are applied on the blocks as shown in the figure. Calculate the frictional force between 4 kg block and ground (Assume initially the tension in the string was just before forces `F_(1)` and `F_(2)` wer applied).

Options

A. 24N
B. 8N
C. 18N
D. 10N

Explanation

System will not move (Equilibrium)
For equilibrium of 2 kg block

`rArr T=2N`
For equilibrium of 4 kg block

`T+f_(2)=20`
`rArr f_(2)=18N`