Straighterline PHY250 General Physics I Graded Exam 2 (New Version June 2024)

Question 1 Correct 6.00 points out of 6.00 A 0.500 kg steel ball is dropped from a height of 4.00 m onto a horizontal steel slab. The collision appears elastic in that the ball rebounds to its original height. If the collision lasts for 2.00 × 10−3 s, which of the following is the impulse imparted to the ball and the average force applied to the ball during the collision? Select one: a. I = 8.49 kg•m / s F = 4.25 × 103 N b. I = 8.85 kg•m / s F = 4.43 × 103 N c. I = 8.00 kg•m / s F = 4.00 × 103 N d. I = 8.86 kg•m / s F = 2.22 × 103 N Straighterline PHY250 General Physics I Graded Exam 2 (New Version June 2024) We are a team of experts offering class attendance for all Straighterline, Online ATI, HESI, NCLEX, Portage Learning, Sophia etc courses (including final proctored exams!!). We also write essays, discussion posts, research papers and school assignments. Should you need any of these services, Contact us via email: or : +1 (540) 753-5914. Guaranteed Passing! PHY250_TW | Chapter 6: The Physics of Extended Objects Started on State Finished Completed on Time taken 55 mins 22 secs GradeQuestion 3 Correct 6.00 points out of 6.00 Where is the center of mass for the rectangle in the figure? Select one: a. In the center of the rectangle b. Directly between 1 and 4 c. Close to 3 d. Near the bottom between 3 and 4 An empty freight train car of mass 10,000 kg is rolling along a level section of track at 2.00 m / s. It collides with a loaded car of weight 1.96 × 105 N, which is at rest. The cars couple upon collision. Which of the following is the speed of the train after the collision? Select one: a. 1.02 m / s b. 0.667 m / s c. 2.00 m / s d. 3.02 m / s Question 2 Correct 6.00 points out of 6.00Question 5 Correct 6.00 points out of 6.00 True or false? Gyroscopes do not need external forces to precess. Select one: a. false b. true Question 6 Correct 6.00 points out of 6.00 Why does an ice skater’s angular velocity increase when she pulls in her arms during a spin? Select one: a. She applies a torque. b. She increases her moment of inertia. c. She reduces her moment of inertia. d. She moves her center of mass. Which of the following is the general definition of impulse ? Select one: → a. ΣF = → d p dt b. →I = ∫t2 ΣF→dt t → c. F 1 → = ddt I d. →I = d (m→v ) dt Question 4 Correct 6.00 points out of 6.00Question 8 Correct 6.00 points out of 6.00 The work done by a variable force F of the form F = kx where x varies from x0 to x1 where x0 = 0 is given by which of the following? Select one: a. kx12 b. kx1 c. (1/2) kx12 d. 0.5kx03 Question 9 Correct 6.00 points out of 6.00 A spaceship is in space and currently at rest. The directive is given to accelerate from rest to a speed of 2.90 × 103 m / s. If the fuel budgeted for this action is 400 kg, which of the following is velocity of the exhaust gas required if the ship mass is 7.38 ×103 kg? Select one: a. 955 [m / s] b. −955 [m / s] c. –5.5 × 104 [m / s] d. −1.01 × 103 [m / s] Which of the following objects has the greatest kinetic energy? Select one: a. an object of mass 4m and speed v b. an object of mass 3m and speed 2v c. an object of mass 2m and speed 3v d. an object of mass m and speed 4v Question 7 Correct 6.00 points out of 6.00Question 11 Correct 6.00 points out of 6.00 Which of the following is not a unit of work? Select one: a. N⋅m b. kg⋅m2/s2 c. J⋅m d. ft ⋅ lb Question 12 Correct 6.00 points out of 6.00 A pendulum bob has mass of 0.750 kg and is on a pendulum arm of length 1.00 m. The pendulum is pulled back so that the arm makes an angle of 60.0° from the vertical and is then released. Which of the following is the speed of the mass when it reaches its lowest point? Select one: a. 3.68 m/s b. 3.13 m/s c. 4.43 m/s d. 4.12 m/s A 1,450 kg car moves with a speed of 25.0 m / s when it collides with a stationary car having a mass of 1,550 kg. The two vehicles lock bumpers on impact. The two cars thencollide with a stationary third car of mass 1,250 kg. During this second impact, the third vehicle becomes attached to the second but the first car is breaks free and moves at 0.125 m / s in the opposite direction. Which of the following is the final velocity of thesecond and third cars after the final collision? Select one: a. 12.88 m / s b. 12.14 m / s c. 14.42 m / s d. 13.01 m / s Question 10 Correct 6.00 points out of 6.00Question 14 Correct 6.00 points out of 6.00 An ocean liner in the distance subtends an arc in your field of vision of 2°. If you estimate the length of the ocean liner to be 250 m, how far away is it? Select one: a. 130 m b. 500 m c. 7200 m d. 14,000 m Question 15 Correct 6.00 points out of 6.00 Which of the following is a form of Hooke’s law, where Fs  is a spring force? Select one: a. Fs = −0.5x b. Fs = –kx c. Fs = −0.5x2 d. Fs = 0.5kx2 An automobile of mass 900 kg is moving at a speed of 12.5 m/s when it encounters a hill. At the bottom of the hill the car speed increases to 14.6 m/s. If the elevation of the hill is 15.3 m, how much work did the brakes do while going down the hill? Select one: a. -1.09x105 J b. -9.59x104 J c. 2.05x105 J d. 1.33x105 J Question 13 Correct 6.00 points out of 6.00A glasscutter has cut the shape below out of a sheet of glass for a unique window. Which of the following correctly shows the location of the center of mass of the window? You can assume that the glass has the same thickness throughout, so that the mass distribution throughout the window is uniform. Select one: a. b. c. d. Question 16 Correct 6.00 points out of 6.00Question 18 Incorrect 0.00 points out of 6.00 A 3800 W electric motor brings a merry-go-round with a moment of inertia 90, 900 kg ⋅ m2 from rest up to a full speed in 15 seconds. Neglecting friction, what is the merry-go-round's full speed? Select one: a. 0.63 rad / s b. 1.1 rad / s c. 1.3 rad / s d. 1.6 rad / s Assume that when the brakes are applied a constant frictional force is exerted on the wheels of a car. Which of the following is correct? Select one: a. The car loses kinetic energy at a constant rate. b. The distance the car travels before coming to rest is proportional to the speed of the car just before the brakes are applied. c. The distance the car travels before coming to rest is proportional to the square of the speed of the car just before the brakes are applied. d. The kinetic energy of the car is inversely proportional to the time, with t = 0 being the instant the brakes are applied. Question 17 Correct 6.00 points out of 6.00Question 20 Correct 6.00 points out of 6.00 At any given instant in the rotational motion of a windmill, one of its blades is closest to pointing straight up (at certain instants, there are two blades that are equally close). Call that blade the “superior” blade at that instant. Starting from rest with one of its five blades pointing straight up, a windmill is angularly accelerated at a constant rate of 4.38 rad / s2. At what angle is the superior blade from vertical exactly 35 seconds later? Select one: a. 6.1 rad b. 9.7 × 10−3 rad c. 1.1 rad d. 0.17 rad Question 21 Correct 6.00 points out of 6.00 Two fruit flies land on a spinning record. One fly lands 0.050 m from the center, while the other lands 0.12 m from the center. What is the ratio of the centripetal force experienced by the first fly to that experienced by the second fly? Assume the two flies have the same mass. Select one: a. 12:5 b. 5:12 c. 144:25 d. 25:144 A 309 g glass rolls down an incline and onto a horizontal platform where it hits a beverage can that is laying at rest on its side. The top of the incline is 11.0 cm above the horizontal platform. The beverage can is initially at rest and weighs 7.35 N. Which of following is the final velocity of the glass? Select one: a. 0.612 m / s b. −5.83 m / s c. −1.35 m / s d. −0.612 m / s Question 19 Correct 6.00 points out of 6.00Question 23 Incorrect 0.00 points out of 6.00 Suppose a wheel with a moment of inertia I = 2.5 kg ⋅ m2 , a radius of R = 40 cm, and a mass of 6 kg were spinning at 4 rad/s before being released. If it rolls without slipping, how fast will it roll? Select one: a. 1.92 m / s b. 1.36 m / s c. 1.85 m / s d. 2.17 m / s A truck weighing 1000 N moves at 5.89 m / s when it has an elastic collision with another vehicle. The second vehicle, weighing 981 N, was stationary but free to move. Which of the following is the final velocity of the first vehicle after the collision? Select one: a. v1 f  = 0.0565 m / s b. v1 f  = 0.00901 m / s c. v1f  = 0.0583 m / s d. v1 f  = 0.00168 m / s Question 22 Correct 6.00 points out of 6.00Question 25 Correct 6.00 points out of 6.00 A truck that weighs 1000 N moves at 5.89 m / s when it hits another vehicle in an elastic collision. The second vehicle, weighing 981 N, was stationary but free to move. Find the final velocity of the second vehicle after the collision. Select one: a. v2 f  = 29.2 m / s b. v2 f  = 5.95 m / s c. v2 f  = 0.0583 m / s d. v2 f  = 58.3 m / s Quiz navigation 1 2 3 4 5 6 7 8 9 10 Show one page at a time Finish review A mass m is dropped from rest to the ground from a height h. Which of the following is correct? Select one: a. When it strikes the ground, the speed of the mass is inversely proportional to h. b. The kinetic energy of the mass when it strikes the ground is inversely proportional to h. c. The kinetic energy of the mass when it strikes the ground is independent of m. d. When it strikes the ground the speed of the mass is independent of m. Question 24 Correct 6.00 points out of 6.00© 2023 StraighterLine. All rights reserved