College Physics I 1401 Spring Final (120 Minutes, 200 Points)Instructor: Dr. Ping Lu Student Name:_____________________________ Grade______________Notes: Please give me your all working on each question.For instance: (15 points)A grocery bagger pushes a 2.00 kg bag of potatoes in such a way that the net external force on it is 65.0 N. Calculate its acceleration.Given: m= 2.00 kg, F= 65.0 NFind: aSolve: From the second law F = ma, so we have a = F/m = 65.0/2.00 = 32.5 (m/s^2)Answer: Its acceleration is 32.5 m/s^2.All working on each question you should have four steps: given, find, solve, and answer. 1. Multiple Choice: total 80 points 1. State how many significant figures are proper in the results of the following calculation:(106.7) (90) (46.210) (1.01)a. 1 b. 2 c. 3 d. 42. State how many significant figures are proper in the results of the following calculation: (5.9)^2a. 1 b. 2 c. 3 d. 43. What is the magnitude of the momentum of a 7000-kg truck whose speed is 20 m/s?Answer:_________4. How much work does a supermarket checkout attendant do on a can of soup he pushes 0.310 m horizontally with a force of 5.20 N? Express your answer in joules and kilocalories.Answer:_________5. The density of brass is 8.6 g/cm3. What is this value in kilograms per cubic meter? _______ kg/m6. Assume that an MX missile goes from rest to a suborbital velocity of 6.0 km/s in 40.0 s. What is its average acceleration in____ m/s^2? What is its average acceleration in multiples of g?______7. A stone is thrown horizontally from the top of a cliff. One second after it has left you hand its vertical distance below the cliff is ______.8. Compared to the mass of a certain object on earth, the mass of the same object on the moon isa. more. b. less. c. the same9. When the net force that acts on a hockey puck is 12 N, the puck accelerates at a rate of 48 m/s/s. Determine the mass of the puck.______10. Calculate the linear acceleration of a car, the 0.30 m radius tires of which have an angular acceleration of 12.0 rad/s2. Assume no slippage.Answer:_______2. Questions: total 120 points1. (10 points) A grocery bagger pushes a 1.00 kg bag of potatoes in such a way that the net external force on it is 20.0 N. Calculate its acceleration.2. (15 points) An ordinary workshop grindstone has a radius of 9.50 cm and rotates at 7000.0 rpm. Calculate the centripetal acceleration at its edge in m/s/s and convert it to multiples of g.3. Suppose a yo-yo has a center shaft 0.300 cm in radius and that string is being pulled from it. (10 points) (a) If the string is stationary and the yo-yo accelerates away from it at a rate of 1.70 m/s2, what is its angular acceleration? (5 points) (b) What is the angular velocity after 0.750 s if it starts from rest?(5) The outside radius of the yo-yo is 3.50 cm. In the reference fram of the yo-yo's mass center, what is the tangential acceleration of a point on its edge?4. Suppose a 57.0-kg gymnast climbs a rope. (a) (8 points)What is the tension in the rope if he climbs at a constant speed? (b) (7 points) What is the tension in the rope if he accelerates upward at a rate of 1.80 m/s2? 5. (15 points) The triceps muscle in the back of the upper arm extends the forearm. This muscle in a professional boxer exerts a force of 2.00 10✕3 N with an effective perpendicular lever arm of 4.00 cm, producing an angular acceleration of the forearm of 130 rad/s2. What is the moment of inertia of the boxer's forearm?6. (8 points) (a) How much gravitational potential energy (relative to the ground on which it is built) is stored in an Egyptian pyramid, given its mass is about 6 10✕9 kg and its center of mass is 28.0 m above the surrounding ground? (7 points) (b) What is the ratio of this energy to the daily food intake of a person (1.2 10✕7 J)?7. (15 points) A 5.50 10✕5 kg subway train is brought to a stop from a speed of 0.600 m/s in 0.900 m by a large spring bumper at the end of its track. What is the force constant k of the spring?8. (8 points) (a) Calculate the force needed to bring a 1000 kg car to rest from a speed of 90.0 km/h in a distance of 116 m (a fairly typical distance for a nonpanic stop).(7 points) (b) Suppose instead the car hits a concrete abutment at full speed and is brought to a stop in 2.00 m. Calculate the force exerted on the car and compare it with the force found in part (a), i.e. find the ratio of the force in part(b) to the force in