Question 39: Laws of Motion

Question

A hanging mass M is connected to a four times bigger mass by using a string-pulley arrangement, as shown in the figure. The bigger mass is placed on a horizontal ice-slab and being pulled by 2 Mg force. In this situation, tension in the string is $${x \over 5}$$ Mg for x = ______________. Neglect mass of the string and friction of the block (bigger mass) with ice slab.
(Given g = acceleration due to gravity)

Accepted Answer

$$a = {{Mg} \over {4M + M}} = {g \over 5}$$ (in upward direction)
$$T = M\left( {g + {g \over 5}} \right) = {{6Mg} \over 5}$$
$$ \Rightarrow x = 6$$

Laws of Motion

Integer / Numeric Answer Type