(D) The rotational kinetic energy of the disc is given by $KE = \frac{1}{2}I\omega^2 = K\theta^2.$From this,we can express the angular velocity $\omeg

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(D) The rotational kinetic energy of the disc is given by $KE = \frac{1}{2}I\omega^2 = K\theta^2.$From this,we can express the angular velocity $\omega$ as:$\omega^2 = \frac{2K\theta^2}{I} \implies \omega = \sqrt{\frac{2K}{I}}\theta \quad \dots(1)$Angular acceleration $\alpha$ is the rate of change of angular velocity with respect to time:$\alpha = \frac{d\omega}{dt} = \frac{d}{dt}\left( \sqrt{\frac{2K}{I}}\theta \right) = \sqrt{\frac{2K}{I}} \frac{d\theta}{dt}$Since $\frac{d\theta}{dt} = \omega,$ we substitute the expression for $\omega$ from equation $(1)$:$\alpha = \sqrt{\frac{2K}{I}} \left( \sqrt{\frac{2K}{I}}\theta \right)$$\alpha = \frac{2K}{I}\theta.$

Class 11 Physics System of Particles and Rotational Motion Relation between Torque and Angular acceleration and it's Application

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$A$ stationary horizontal disc is free to rotate about its axis. When a torque is applied on it,its kinetic energy as a function of $\theta,$ where $\theta$ is the angle by which it has rotated,is given as $K\theta^2.$ If its moment of inertia is $I,$ then the angular acceleration of the disc is

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A
$\frac{K}{I}\theta$
B
$\frac{K}{2I}\theta$
C
$\frac{K}{4I}\theta$
D
$\frac{2K}{I}\theta$

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System of Particles and Rotational Motion

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Relation between Torque and Angular acceleration and it's Application

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$A$ wheel rotates at $720 \ rpm$ about an axis passing through its center. It is brought to rest by applying a constant torque for $8 \ s$. What is the value of the torque in $Nm$? (Given: $I = \frac{24}{\pi} \ kg \cdot m^2$)

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$A$ flywheel of moment of inertia $0.4 \, kg \, m^2$ and radius $0.2 \, m$ is free to rotate about a central axis. If a string is wrapped around it and it is pulled with a force of $10 \, N$,then the angular velocity after $4 \, s$ will be ......... $rad \, s^{-1}$.

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Two equal and opposite forces are applied tangentially to a uniform disc of mass $M$ and radius $R$ as shown in the figure. If the disc is pivoted at its centre and free to rotate in its plane,the angular acceleration of the disc is ............

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$A$ torque of $30 \, N \cdot m$ is applied for $10 \, s$ on a wheel of mass $5 \, kg$ and moment of inertia $2 \, kg \cdot m^2$. The angular displacement of the wheel in $10 \, s$ will be ....... radians.

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The moment of inertia of a wheel about an axis passing through its center is $200 \, kg \cdot m^2$. $A$ constant torque of $1000 \, N \cdot m$ is applied to rotate the wheel. After $3 \, s$,the angular velocity of the wheel will be ........ $rad/s$.

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$A$ stationary horizontal disc is free to rotate about its axis. When a torque is applied on it,its kinetic energy as a function of $\theta,$ where $\theta$ is the angle by which it has rotated,is given as $K\theta^2.$ If its moment of inertia is $I,$ then the angular acceleration of the disc is

Similar Questions

$A$ wheel rotates at $720 \ rpm$ about an axis passing through its center. It is brought to rest by applying a constant torque for $8 \ s$. What is the value of the torque in $Nm$? (Given: $I = \frac{24}{\pi} \ kg \cdot m^2$)

$A$ flywheel of moment of inertia $0.4 \, kg \, m^2$ and radius $0.2 \, m$ is free to rotate about a central axis. If a string is wrapped around it and it is pulled with a force of $10 \, N$,then the angular velocity after $4 \, s$ will be ......... $rad \, s^{-1}$.

Two equal and opposite forces are applied tangentially to a uniform disc of mass $M$ and radius $R$ as shown in the figure. If the disc is pivoted at its centre and free to rotate in its plane,the angular acceleration of the disc is ............

$A$ torque of $30 \, N \cdot m$ is applied for $10 \, s$ on a wheel of mass $5 \, kg$ and moment of inertia $2 \, kg \cdot m^2$. The angular displacement of the wheel in $10 \, s$ will be ....... radians.

The moment of inertia of a wheel about an axis passing through its center is $200 \, kg \cdot m^2$. $A$ constant torque of $1000 \, N \cdot m$ is applied to rotate the wheel. After $3 \, s$,the angular velocity of the wheel will be ........ $rad/s$.

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