If the human body could convert a candy bar directly into work, how high could a 76 kg man climb a ladder if he were fueled by one bar (=1100 kJ)?

If the man then jumped off the ladder, what will be his speed when he reaches the bottom?

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A 63 kg skier starts from rest at the top of a ski jump, point A in the figure, and travels down the ramp. If friction and air resistance can be neglected, determine

(a) her speed v_{B} when she reaches the horizontal end of the ramp at B

(b) the distance s to
where she strikes the ground
at C

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A projectile is fired at an upward angle of 48.0° from the top of a 130-m-high cliff with a speed of 180 m/s. What will be its speed when it strikes the ground below? (Use conservation of energy. Neglect air resistance.)

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A bicyclist coasts down a 6.5 degree hill at a steady speed of 4.5 m/s. Assuming a total mass of 75 kg (bicycle plus rider), what must be the cyclists power output to climb the same hill at the same speed?

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The position of a 260 g object is given (in meters) by x = 5.0t^{3} - 8.0t^{2} - 45t, where t is in seconds.

(a) Determine the net rate of work done on this object at t =2.1 s.

(b) Determine the net rate of work done on this object at t = 4.1 s.

(c) What is the average net power input during the interval from t = 0 to t = 2.1 s?

(d) What is the average net power input during the interval from t =2.1 s to t=4.1 s?

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