One end of a string of length 1.0 m is tied to a body of mass 0.5 kg. It is whirled in a vertical circle as shown in fig. If the angular frequency of the body is 4 rad s–1, what is the tension in the strong when the body is at the topmost point A? Take g = 10 ms–2.
Speed of the body (v) = Rω = 1.0 × 4 = 4 ms –1.
Referring to fig, we find that, when the body is at the topmost point A, the tension in the string is
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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–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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Take g = 10 ms–2.
One end of a string of length R is tied to a stone of mass m and the other end to a small pivot on a frictionless vertical board. The stone is whirled in a vertical circle with the pivot as the centre. The minimum speed the stone must have, when it is at the topmost point on the circle, so that the string does not slack is given by
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A simple pendulum of length r and bob mass m swings in a vertical circle with angular frequency ω. When the string makes an angle θ with the vertical, the speed of the bob is v. The radical acceleration of the bob at this instant is given by