Question:
A uniform disc of mass $0.5\, kg$ and radius $r$ is projected with velocity $18 \,m / s$ at $t=0$ s on a rough horizontal surface It starts off with a purely sliding motion at $t=0\, s$ After $2\, s$ it acquires a purely rolling motion (see figure) The total kinetic energy of the disc after $2 \,s$ will be ______ $J$ (given, coefficient of friction is $0.3$ and g=10m/s2)
A uniform disc of mass $0.5\, kg$ and radius $r$ is projected with velocity $18 \,m / s$ at $t=0$ s on a rough horizontal surface It starts off with a purely sliding motion at $t=0\, s$ After $2\, s$ it acquires a purely rolling motion (see figure) The total kinetic energy of the disc after $2 \,s$ will be ______ $J$ (given, coefficient of friction is $0.3$ and g=10m/s2)
Updated On: Mar 19, 2025
Hide Solution
Verified By Collegedunia
Correct Answer: 54
Solution and Explanation
The correct answer is 54.
Was this answer helpful?
3
0
Top Questions on Rotational motion
- A thin spherical shell of radius \( 0.5 \, \text{m} \) and mass \( 2 \, \text{kg} \) is rotating about its axis of symmetry with an angular velocity of \( 10 \, \text{rad/s} \). What is its moment of inertia?
- MHT CET - 2025
- Physics
- Rotational motion
- If the displacement of a particle executing simple harmonic motion is given by \( x = 0.5 \cos(125.6\,t) \), then the time period of oscillation of the particle is nearly (Here \(x\) is displacement in metre and \(t\) is time in second)
- AP EAPCET - 2025
- Physics
- Rotational motion
- The apparent weight of a girl of mass 30 kg when she is in a lift moving vertically upwards with an acceleration of \( 2~\text{ms}^{-2} \) is
(Acceleration due to gravity = \( 10~\text{ms}^{-2} \))- AP EAPCET - 2025
- Physics
- Rotational motion
- A solid sphere and a solid cylinder have same mass and same radius. The ratio of the moment of inertia of the solid sphere about its diameter and the moment of inertia of the solid cylinder about its axis is:
- AP EAPCET - 2025
- Physics
- Rotational motion
- If the velocity at the maximum height of a projectile projected at an angle of \(45^\circ\) is \(20 \, \text{m/s}\), then the maximum height reached by the projectile is:
- AP EAPCET - 2025
- Physics
- Rotational motion
View More Questions
Questions Asked in JEE Main exam
- The expression given below shows the variation of velocity \( v \) with time \( t \): \[ v = At^2 + \frac{Bt}{C + t}. \] The dimension of \( ABC \) is:
- JEE Main - 2025
- Thermodynamics terms
- The elemental composition of a compound is 54.2%C, 9.2%H, and 36.6%O. If the molar mass of the compound is 132 g/mol, the molecular formula of the compound is:
- JEE Main - 2025
- Thermodynamics
Let A be a 3 × 3 matrix such that \(\text{det}(A) = 5\). If \(\text{det}(3 \, \text{adj}(2A)) = 2^{\alpha \cdot 3^{\beta} \cdot 5^{\gamma}}\), then \( (\alpha + \beta + \gamma) \) is equal to:
- JEE Main - 2025
- Matrix Operations
- Let \( P_n = \alpha^n + \beta^n \), \( P_{10} = 123 \), \( P_9 = 76 \), \( P_8 = 47 \), and \( P_1 = 1 \). The quadratic equation whose roots are \( \frac{1}{\alpha} \) and \( \frac{1}{\beta} \) is:
- JEE Main - 2025
- Sequences and Series
- Number of functions \( f: \{1, 2, \dots, 100\} \to \{0, 1\} \), that assign 1 to exactly one of the positive integers less than or equal to 98, is equal to:
- JEE Main - 2025
- Vectors
View More Questions
Concepts Used:
Rotational Motion
Rotational motion can be defined as the motion of an object around a circular path, in a fixed orbit.
Rotational Motion Examples:
The wheel or rotor of a motor, which appears in rotation motion problems, is a common example of the rotational motion of a rigid body.
Other examples:
- Moving by Bus
- Sailing of Boat
- Dog walking
- A person shaking the plant.
- A stone falls straight at the surface of the earth.
- Movement of a coin over a carrom board
Types of Motion involving Rotation:
- Rotation about a fixed axis (Pure rotation)
- Rotation about an axis of rotation (Combined translational and rotational motion)
- Rotation about an axis in the rotation (rotating axis)