The length of second’s hand in a watch is $$1\,cm.$$ The change in velocity of its tip in 15 seconds is:
A.
zero
B.
$$\frac{\pi }{{30\sqrt 2 }}cm/s$$
C.
$$\frac{\pi }{{30}}cm/s$$
D.
$$\frac{{\pi \sqrt 2 }}{{30}}cm/s$$
Answer :
$$\frac{{\pi \sqrt 2 }}{{30}}cm/s$$
Solution :
$$\Delta v = \sqrt 2 v = \sqrt 2 \omega r = \sqrt 2 \left( {\frac{{2\pi }}{{60}}} \right) \times 1 = \frac{{\pi \sqrt 2 }}{{30}}cm/s$$
Releted MCQ Question on Basic Physics >> Kinematics
Releted Question 1
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