A 4.2-m-diameter merry-go-round is rotating freely with an angular

A 4.2-m-diameter merry-go-round is rotating freely with an angular A 4.2-m-diameter merry-go-round is rotating freely with an angular velocity of 0.80 rad/s. Its total moment of inertia is 1360 kg/m2.  Four people standing on the ground, each of mass 65 kg, suddenly step onto the edge of the merry-go-round. (a) What is the angular velocity […]

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A 2.00-kg rock has horizontal velocity of magnitude

A 2.00-kg rock has horizontal velocity of magnitude A 2.00-kg rock has horizontal velocity of magnitude 12.0 m/s when it is at point Pin Fig. 10.47. (a) At this instant, what are the magnitude and direction of its angular momentum relative to point O? (b) If the only force acting on the rock is its […]

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A 5.00-kg ball is dropped from a height of 12.0 m

A 5.00-kg ball is dropped from a height of 12.0 m above one end of a uniform bar that pivots at its center. The bar has mass 8.00 kg and is 4.00 m in length. At the oilier end of the bar sits another 5.00-kg ball, unattached to the bar. The dropped ball sticks to […]

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A 55-kg person riding a bike puts all her weight

A 55-kg person riding a bike puts all her weight A 55-kg person riding a bike puts all her weight on each pedal when climbing a hill. The pedals rotate in a circle of radius 17cm. (a) What is the maximum torque she exerts? (b) How could she exert more torque? Is this the question […]

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Radio announcers who still play vinyl records have to be

Radio announcers who still play vinyl records have to be Radio announcers who still play vinyl records have to be careful when cuing up live recordings. While studio albums have blank spaces between the songs, live albums have audiences cheering. If the volume levels are left up when the turntable is turned on, it sounds […]

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One blade of a pair of scissors rotates counterclockwise in

One blade of a pair of scissors rotates counterclockwise in One blade of a pair of scissors rotates counterclockwise in the xy plane. What is the direction of w? What is the direction of a if the magnitude of the angular velocity is decreasing in time? Is this the question you were looking for? If […]

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A 392-N wheel comes off a moving truck

A 392-N wheel comes off a moving truck A 392-N wheel comes off a moving truck and rolls without slipping along a highway. At the bottom of a hill it is rotating at 25.0 rad/s. The radius of the wheel is 0.600 m, and its moment of inertia about its rotation axis is O.800MR’. Friction […]

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A 32.0 kg wheel, essentially a thin hoop with radius

A 32.0 kg wheel, essentially a thin hoop with radius A 32.0 kg wheel, essentially a thin hoop with radius 1.20 m, is rotating at 280 rev/min. It must be brought to a stop in 15.0 s. (a) How much work must be done to stop it? (b) What is the required average power? Is […]

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A 21-speed bicycle has seven sprockets at the rear wheel

A 21-speed bicycle has seven sprockets at the rear wheel A 21-speed bicycle has seven sprockets at the rear wheel and three at the pedal cranks. In which gear is it harder to pedal, a small rear sprocket or a large rear sprocket? Why? In which gear is it harder to pedal, a small front […]

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