Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Advanced 2007Paper 1
Exam
JEE Advanced
Year
2007
Paper
Paper 1
Subject
Physics
Chapter
Laws of Motion

JEE Advanced 2007 · Paper 1 · Physics · Laws of Motion

Two particles of mass m each are tied at the ends of a light string...

Two particles of mass mm each are tied at the ends of a light string of length 2a2 a. The whole system is kept on a frictionless horizontal surface with the string held tight so that each mass is at a distance aa from the centre PP (as shown in the figure). Now, the mid-point of the string is pulled vertically upwards with a small but constant force FF. As a result, the particles move towards each other on the surface. The magnitude of acceleration, when the separation between them becomes 2x2 x, is Two particles of mass m each are tied at the ends of a light string of length 2 a . The whole system is kept on a

Options

  1. AF2maa2−x2\frac{F}{2 m} \frac{a}{\sqrt{a^2-x^2}}
  2. BF2mxa2−x2\frac{F}{2 m} \frac{x}{\sqrt{a^2-x^2}}
  3. CF2mxa\frac{F}{2 m} \frac{x}{a}
  4. DF2ma2−x2x\frac{F}{2 m} \frac{\sqrt{a^2-x^2}}{x}

Correct answer

B. F2mxa2−x2\frac{F}{2 m} \frac{x}{\sqrt{a^2-x^2}}

Step-by-step solution

6. 2Tcos⁡θ=F∴T=F2sec⁡θ Acceleration of particle =Tsin⁡θm=Ftan⁡θ2m=F2mxa2−x2\begin{aligned}& 2 T \cos \theta=F \\ & \therefore T=\frac{F}{2} \sec \theta\\ & \text{ Acceleration of particle }=\frac{T \sin \theta}{m}=\frac{F \tan \theta}{2 m}=\frac{F}{2 m} \frac{x}{\sqrt{a^2-x^2}} \end{aligned}\therefore \text{ Option (b) is correct. }$Two particles of mass m each are tied at the ends of a light string of length 2 a . The whole system is kept on a
Practice Laws of Motion on Quantrex Academy →

More from Laws of Motion

A block takes t time to slide down a plane inclined at 45° to the horizontal. If the… JEE Main 2026Two blocks ( P and Q ) with respectively masses 2 kg and 1.5 kg are joined by a massless… JEE Main 2026A mass of 1 kg is kept on an inclined plane with 30° inclination with respect to… JEE Main 2026Three masses m_1 = 4 kg, m_2 = 4 kg and m_3 = 6 kg are suspended from a fixed smooth… JEE Main 2026A wedge Y with mass of 10 kg and all frictionless surfaces and the inclined surface… JEE Main 2026At t=0 , a body of mass 100 g starts moving under the influence of a force (5 i +10 j )… JEE Main 2026The time taken by a block of mass m to slide down from the highest point to the lowest… JEE Main 2026A 0.5 kg mass is in contact against the inner wall of a cylindrical drum of radius 4 m… JEE Main 2026 Full Laws of Motion list All JEE Advanced PYQs