Question 14 (1 point) A spring has an elastic constant of 8.75 x 10-N/m. What is the magnitude of the force required to stretch this spring a distance of 28.6 cm from its equilibrium position? 3.06 x 102 N 7.16 x 102 N O 2.50 x 103 N O 3.06 x 103 NQuestion 15 (1 point) A force of 56.0 N does work over a displacement of 24.5 m. If the angle between the force and the displacement is 35.0, what is the work done by this force? 1.37 x 103 J 1.12 x 103 ] 9.61 x 102 1 7,87 x 102 JQuestion 16 (1 point) A roller coaster trolley with a mass of 2.30 x 10 kg begins to coast up a hill at a point 4.25 m above the ground. The trolley has an initial speed of 16.5 m/s. At the top of the hill that is 19.6 m above the ground, the trolley has a speed of 1.12 m/s. What is the work done on the trolley as it coasts up the hill? 6.58 x 105 ) 6.00 x 104 J 3.47 x 104 J 3.32 x 104 )Question 17 (1 point) The pendulum has a length of 1.20 m and a bob of mass 2.50 kg. The pendulum bob is pulled sideways until it is 30.8 cm above its rest position. What will be its kinetic energy when it passes through the lowest point of its motion? 2.46J 5.92 J 6.04 1 7.55 JQuestion 18 (1 point) A winch motor generates a power of 55.0 KW when it is used to lift a 6.50 x 102 kg bucket of concrete to a height of 75.0 m. If the time required to do this is 25.0 s, what is the efficiency of this system? O 26.5% O 27.8% 29.6% O 34.8%Question 19 (1 point) In terms of kg, m, and s, which of the following is the unit for power? O kam 5 3 O karn korn?Question 20 (4 points) A roller coaster car has a mass of 290 kg. Starting from rest, the car acquires 3.13 x 10 Joules of kinetic energy as it descends to the bottom of a hill in 5.3 seconds. a. Calculate the height of the hill. [Neglect friction.] b. Calculate the speed of the roller coaster car at the bottom of the hill. C. Calculate the magnitude of the average acceleration of the roller coaster car as it descends to the bottom of the hill.Question 21 (2 points) A pop-up toy has a mass of 0.020 kg and a spring constant of 150 N/m. A force is applied to the toy to compress the spring 0.050 meter (see the following Figure). Force Suction cup 8 Spring that compresses Base a. Calculate the potential energy stored in the compressed spring. b. The toy is activated and all the compressed spring's potential energy is converted to gravitational potential energy. Calculate the maximum vertical height to which the toy is propelled