A uniform disk of mass \(50\) \(kg\) is rolling without slipping with a speed of \(0.4 \;m/s\). Find minimum energy required to bring the disk to rest (in \(J\)).
Solution and Explanation
The Correct Answer is : \(6\) \(J\)
\(KE=\frac{1}{2}mv^2_{ω}+\frac{1}{2}(\frac{mr^2}{2})ω^2\)
\(K=\frac{3}{4}mv^2\)
\(=\frac{3}{4}\times50\times(4)\times(0.4)\)
\(=6 \ \text{J}\)
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Concepts Used:
Speed and Velocity
The rate at which an object covers a certain distance is commonly known as speed.
The rate at which an object changes position in a certain direction is called velocity.
Difference Between Speed and Velocity:
Read More: Difference Between Speed and Velocity