The position vector of 1 kg object is
\(\stackrel{→}{r} = (3\hat{i} - \hat{j}) m\)
and its velocity
\(\stackrel{→}{v} = (3\hat{j} +\hat{k}) ms^{-1}.\)
The magnitude of its angular momentum is √x Nm where x is
The position vector of 1 kg object is
\(\stackrel{→}{r} = (3\hat{i} - \hat{j}) m\)
and its velocity
\(\stackrel{→}{v} = (3\hat{j} +\hat{k}) ms^{-1}.\)
The magnitude of its angular momentum is √x Nm where x is
Correct Answer: 91
Solution and Explanation
The correct answer is 91
\(| \stackrel{→}{i} | = | \stackrel{→}{r} × (m\stackrel{→}{v}) |\)
\(= | ( 3\hat{i} - \hat{j} ) × ( 3\hat{j} + \hat{k} ) |\)
\(= | -\hat{i} - 3\hat{j} + 9\hat{k} |\)
\(= \sqrt{91}\)
Therefore The magnitude of its angular momentum is \(\sqrt{x}\) Nm where x is \(\sqrt{91}\)
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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)