Problem 4: A child of mass m = 24 kg slides down a slide of height h = 2.5 m without friction. Let gravitational potential energy be zero at ground level. Part (a) Write an expression for the child's total mechanical energy, E, at the top of the slide, in terms of the variables in the problem and the acceleration due to gravity g. Expression : E = Select from the variables below to write your expression. Note that all variables may not be required. a, B, 0, a, b, d, g, h, i, j, k, m, P, S, t Part (b) Calculate the change in the child's potential energy, 4U in joules, from the top to the bottom of the slide at ground level (i.e. AU = Uground - Utop). Numeric : A numeric value is expected and not an expression. AU = Part (c) What is the child's final speed, vin m/s? Numeric : A numeric value is expected and not an expression.Problem 5: A roller coaster car has a speed of vo = 6.9 mis as it tops the crest of a h = 27.5 m drop. What is the car's speed at the bottom of the drop, vin m/s? Numeric : A numeric value is expected and not an expression. Vf= Problem 6: A 60.0 kg skier with an initial speed of 12 m/s coasts up a 2.50 m high rise as shown in the figure. VI = ? KE Vi 350 2.5 m Otheexpertta.com Find her final speed right at the top, in meters per second, given that the coefficient of friction between her skis and the snow is 0.35. Numeric : A numeric value is expected and not an expression. Problem 7: Suppose a car approaches a hill and has an initial speed of 116 km/h at the bottom of the hill. The driver takes her foot off of the gas pedal and allows the car to coast up the hill. Part (a) If the car has the initial speed stated at a height of h = 0, how high, in meters, can the car coast up a hill if work done by friction is negligible? Numeric : A numeric value is expected and not an expression. ho = Part (b) If, in actuality, a 720-kg car with an initial speed of 116 km/h is observed to coast up a hill and stops at a height 23.5 m above its starting point, how much thermal energy was generated by friction in J? Numeric : A numeric value is expected and not an expression. Ef Part (c) What is the magnitude of the average force of friction, in newtons, if the hill has a slope 2.60 above the horizontal? Numeric : A numeric value is expected and not an expression. IFd =Problem 1: A 4.: x 105 kg subway train is brought to a stop from a speed off}. '5 [ms in .5255 ['(1 by a large spring bumper at the end ot'its track. What is the force constant k of the spring in me? Numeric : A numeric value is expected and not an expression. k : Problem 2: A rock is thrown from a bridge 1\". F m above water with an initial speed of H m.-'s. Assuming negligible air resistance, what is the speed that the rock hits the water with, in meters per second? Numeric : A numeric value is expected and not an expression. vf = Problem 3: A basketball player throws a basketball in 1 kg straight up with an initial speed oft-n (1.5 nu's. The ball leaves his hand at shoulder height Ira _'.H.~' tn. Let gravitational potential energy be zero at ground level. Part (a) Give the total mechanical energy of the ball E in terms of maximum height hm it reaches, the mass m, and the gravitational acceleration g. Expression E : Select from the variables below to write your expression. Note that all variables may not be required. 0., I}: I]: 0:! d! g: hm: ho: in j: k: m: P: t: v0 Part (b) What is the height, km in meters? Numeric : A numeric value is expected and not an expression. hm