Two bodies of masses 10 kg and 20 kg respectively kept on a smooth , horizontal surface are tied to the ends of a light string are tied to the ends of a light string are tied to the ends of a light string , a horizontal force f = 60 N is applied to (i) A, (ii) B along the direction of string .What is the direction of string . What is tension in the string in each case ?

Explanation

Here , F = 500 N
`m_(1) = 10 kg , m_(2) = 20 kg`
Let T be the tension in the string and a be the acceleration of the system , in the direction of the force applied .
` a = F/(m_(1)+m_(2)) = 500/(10 +20) = 50/3 m//s^(2)`
(a) when force is applied on higher block , fig3(b)
`T = m_(2)a= 20 xx 50/3 N `
` = 333. 33 N `
Which is different from valueT in case (a) Hence oue answer depends on which mass end , the force is applied .
Note : When two bodies of masses m and M are in contact with each other and a is applied on the combination the acceleration (a) is same and does not depend on whether force is contact depends on whether force is applied on m (or) M .