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 5X Mg for x= ____. Neglect mass of the string and friction of the block (bigger mass) with ice slab. (Given g= acceleration due to gravity)
Answer: 6
Solution
For the system, apply Newton's second law to both masses. For the 4M mass: 2Mg−T=4Ma. For the hanging mass M: T−Mg=Ma. Adding these equations: Mg=5Ma, so a=5g. Substituting back: T=Mg+Ma=Mg+M5g=56Mg. Therefore, x=6.
JEE Main · 2022 · 28 Jun 2022 · Shift 1 · Integer answer