Question
A disc, initially at rest, is rotated about its axis with a uniform angular acceleration. In the first two seconds, it rotates through an angle θ. In the next two seconds, the disc will rotate through an angle

θ



medium
Solution
= initial angular speed and α is the angular acceleration, Since ω_{0} = 0, we have
Therefore, change in angle = 8α – 2α = 6α, which is 3θ.
SIMILAR QUESTIONS
A body moves along a circular track of radius 20 cm. It starts from one end of a diameter, moves along the circular track and reaches the other end of the diameter is 5 seconds. What is the angular speed of the body?
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A stone, tied to the end of a string of length 50 cm, is whirled in a horizontal circle with a constant speed. If the stone makes 40 revolutions in 20 s, what is the speed of the stone along the circle?
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A simple pendulum of length L and with a bob of mass M is oscillating in a plane about a vertical line between angular limits
–Ï• and +Ï•. For an angular displacement θ (< Ï•) the tension is the string and the velocity of the bob are T and v respectively. The flowing relations hold good under the above conditions:
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