A child, m = 25.0 kg, swings from a rope, L = 8.57 m, which hangs above water, d = 1.1 m, when vertical. The child is h = 7.1 m above the water when she begins to swing. Part A: Write an expression for the velocity v of the student at the bottom of the swing. Part B: Assume the child lets go at the bottom of the swing. How long does she take to reach the water, t in seconds?

A block is sent up an incline with a velocity of 3.51 m/s. Assume there is no friction between the incline and the block. The angle is at an incline of 31.1 degrees with the horizontal. A) How far up the incline does the block go? B) How long does it take to get there? C) What is it's speed when it gets back to the bottom?

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77 X 7. A roller coaster reaches the top of the steepest hill with a speed of 6.80 km/h. It then descends the hill, which is at an average angle of 40° and is 59.0 m long. What will its speed be when it reaches the bottom? Assume Hk = 0.16. m/s E C 4 F T G B MacBook Air H U N J WA M K MOSISO भ command option

You want to lift a heavy box with a mass L = 89.0 kg using the two-ideal pulley system as shown. With what minimum force do you have to pull down on the rope in order to lift the box at a constant velocity? One pulley is attached to the ceiling and one to the box. L kg N

A cyclist coasts up a 10.0 degree slope, traveling 20.0 m along the road to the top of the hill. If the cyclist’s ini- tial speed is 9.00 m/s, what is the final speed? Ignore friction and air resistance

The diagram shows all the forces on an object with mass m = magnitude of the acceleration of the object? 89 kg. What is the 480 N Select one: O 9.4 m/s? 30° O 6.0 m/s? 3.0 m/s? 120 N O 4.5 m/s sine and cosine reversed. Check that you didn't get 11.5 m/s? 240 N

A 38.0-kg child swings in a swing supported by two chains, each 3.08 m long. The tension in each chain at the lowest point is 420 N. (a) Find the child's speed at the lowest point. m/s (b) Find the force exerted by the seat on the child at the lowest point. (Ignore the mass of the seat.) N (upward) Need Help? Read Master

1. A box is being pulled up a 40° incline by a 7.0 kg block suspended from a frictionless, massless pulley. The box does not start at the very bottom of the incline. The block is suspended 2.0 m above the ground. The coefficient of kinetic friction between the box and the incline is 0.40. The block is released from rest. At the moment the block hits the ground, the box is traveling at 2.0 m/s up the incline. What is the mass of the box?

A 45.0-kg child swings in a swing supported by two chains, each 3.10 m long. The tension in each chain at the lowest point is 340 N. Find the child's speed at the lowest point. m/s