A 2.0-m long string is tied to a 3.0-kg rock and the rock is twirled around in a circle at a constant speed.The speed of the rock is such that the string makes an angle of 45 degrees with the horizontal.How long does it take the rock to complete one full circle?
A)1.3 s
B)1.9 s
C)2.4 s
D)2.8 s
E)4.4 s

Question

Quizplus · Accepted Answer

The tension in the string provides the centripetal force and a component to balance the weight of the rock. Using trigonometry and the centripetal force formula, we can find the speed and then the period of rotation. The calculations show that the time to complete one full circle is approximately 2.4 seconds.

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