JEE Advanced · Physics · 8. Rotational Motion
A pendulum consists of a bob of mass \(m=0.1 \mathrm{~kg}\) and a massless inextensible string of length \(L=1.0 \mathrm{~m}\). It is suspended from a fixed point at height \(H=0.9 \mathrm{~m}\) above a frictionless horizontal floor. Initially, the bob of the pendulum is lying on the floor at rest vertically below the point of suspension. A horizontal impulse \(P=0.2 \mathrm{~kg}-\mathrm{m} / \mathrm{s}\) is imparted to the bob at some instant. After the bob slides for some distance, the string becomes taut and the bob lifts off the floor. The magnitude of the angular momentum of the pendulum about the point of suspension just before the bob lifts off is \(J \mathrm{~kg}-\mathrm{m}^{2} / \mathrm{s}\). The kinetic energy of the pendulum just after the liftoff is \(K\) Joules.
The value of is ____.
- A 0.15
- B 0.16
- C 0.17
- D 0.18
Answer & Solution
Correct Answer
(B) 0.16
Step-by-step Solution
Detailed explanation
The magnitude of the angular momentum of the pendulum about the point of suspension just before the bob lifts off is, Angular momentum about top point
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- Four combinations of two thin lenses are given in List I. The radius of curvature of all curved surfaces is r and the refractive index of all the lenses is 1.5. Match lens combinations in List I with their focal length in List II and select the correct answer using the code given below the lists.
List I List II A. 
B. 
C. 
D.
JEE Advanced 2014 Medium - When water is filled carefully in a glass, one can fill it to a height above the rim of the glass due to the surface tension of water. To calculate just before water starts flowing, model the shape of the water above the rim as a disc of thickness having semicircular edges, as shown schematically in the figure. When the pressure of water at the bottom of this disc exceeds what can be withstood due to the surface tension, the water surface breaks near the rim and water starts flowing from there. If the density of water, its surface tension and the acceleration due to gravity are and respectively, the value of (in )is ________.
JEE Advanced 2020 Hard - Two large, identical water tanks, 1 and 2, kept on the top of a building of height \(H\), are filled with water up to height \(h\) in each tank. Both the tanks contain an identical hole of small radius on their sides, close to their bottom. A pipe of the same internal radius as that of the hole is connected to tank 2 , and the pipe ends at the ground level. When the water flows from the tanks 1 and 2 through the holes, the times taken to empty the tanks are \(t_1\) and \(t_2\), respectively. If \(H=\left(\frac{16}{9}\right) h\), then the ratio \(t_1 / t_2\) is _______ .JEE Advanced 2024 Medium
- A parallel plate capacitor of capacitance has spacing d between two plates having area The region between the plates is filled with dielectric layers, parallel to its plates, each with thickness The dielectric constant of the layer is For a very large the capacitance is The value of will be____
is the permittivity of free space]JEE Advanced 2019 Hard - Consider a spherical gaseous cloud of mass density in free space where is the radial distance from its center. The gaseous cloud is made of particles of equal mass m moving in circular orbits about the common center with the same kinetic energy . The force acting on the particles is their mutual gravitational force. If is constant in time, the particle number density is: [ is universal gravitational constant]JEE Advanced 2019 Hard
- Statement 1 The sensitivity of a moving coil galvanometer is increased by placing a suitable magnetic material as a core inside the coil.
and Statement 2 Soft iron has a high magnetic permeability and cannot be easily magnetized or demagnetized.JEE Advanced 2008 Easy
More PYQs from JEE Advanced
- Let be a complex number satisfying , where denotes the complex conjugate of . Let the imaginary part of be nonzero.
Match each entry in List-I to the correct entries in List-II.List - I List - II (P) \(|z|^2\) is equal to (1) 12 (Q) \(|z-\bar{z}|^2\) is equal to (2) 4 (R) \(|z|^2+|z+\bar{z}|^2\) is equal to (3) 8 (S) \(|z+1|^2\) is equal to (4) 10 (5) 7
The correct option isJEE Advanced 2023 Hard - Paragraph:
Let \(f:[0,1] \rightarrow \mathbb{R}\) (the set of all real numbers) be a function. Suppose the function \(f\) is twice differentiable, \(f(0)=f(1)=0\) and satisfies \(f^{\prime \prime}(x)-2 f^{\prime}(x)+f(x) \geq e^{x}, x \in[0,1] .\)
Question:
If the function \(\mathrm{e}^{-x} f(x)\) assumes its minimum in the interval \([0,1]\) at \(x=\frac{1}{4}\), which of the following is true?JEE Advanced 2013 Hard - Figure 1 shows the configuration of main scale and Vernier scale before measurement. Fig. 2 shows the configuration corresponding to the measurement of diameter \(D\) of a tube. The measured value of \(D\) is:
JEE Advanced 2025 Easy - The shape of \(\mathrm{XeO}_{2} \mathrm{~F}_{2}\) molecule isJEE Advanced 2012 Medium
- A block of base \(10 \mathrm{~cm} \times 10 \mathrm{~cm}\) and height \(15 \mathrm{~cm}\) is kept on an inclined plane. The coefficient of friction between them is \(\sqrt{3}\). The inclination \(\theta\) of this inclined plane from the horizontal plane is gradually increased from \(0^{\circ}\). Then,JEE Advanced 2009 Medium
- Let and denotes the lines
and
respectively. If is a line which is perpendicular to both and and cuts both of them, then which of the following options describe(s) ?JEE Advanced 2019 Medium