A particle moves uniformly in a circle of radius \(R\) with a speed \(v.\) The average acceleration of the particle in one complete revolution is:
1. \(\dfrac{v^2}{R}\) 2. \(\dfrac{v^2}{2R}\)
3. \(\dfrac{v^2}{\pi R}\) 4. zero
Subtopic:  Acceleration |
 63%
Level 2: 60%+
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\(ABCD\) is a smooth, horizontal, square board of dimension \(2~\text m\times2~\text m.\) A small ball, lying at the centre \(O,\) is given an initial velocity \(\vec v\) so that it rebounds elastically off the edges \(AB\) and \(CD,\) and reaches the corner \(B.\) The time required for the entire motion is \(2~\text s.\) The axes are shown in the figure.

The average acceleration of the ball is:
1. \(\dfrac{1}{4}\left(\hat i+\hat j\right)~\text{m/s}^2\)
2. \(\left(\hat i+\hat j\right)~\text{m/s}^2\)
3. \(\dfrac{1}{2\sqrt2}\left(\hat i+\hat j\right)~\text{m/s}^2\)
4. zero
Subtopic:  Acceleration |
 73%
Level 2: 60%+
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