Two block of mass 4 kg and 2 kg are attached by an inextensible light string as shown in figure. Both the blocks are pulled vertically upwards by a force F=120N
Find
(a) the acceleration of the blocks
(b) tension in the string. (Take g=`10 ms^(-2)`)

Explanation

(a) Let a be the acceleration of the block and T the tension, in the two strings as shown in figure.

Taking the two blocks and the string as the system shown in figure Fig.`8.62`.
Using `sumF_(Y) = ma_(Y)`, we get
`F - 4kg - 2kg = (4 + 2)_a`
or `120 - 40 - 20 = 6_(a)` or `:. a=10m//s^(2)`