1) 1. What quantity describes the ability of a force to rotate an object? a) A. mass b) B. moment of inertia c) C. torque d) D. velocity 2) When two children of different weights balance on a seesaw, they each produce how much torque? a) A. equal torques b) B. unequal torques c) C. equal torques in the same direction d) D. equal torques in the opposite direction 3) The moment of inertia of an object is greater when most of the mass is located? a) A. off-center b) B. near the axis c) C. on the rotational axis d) D. away from the rotational axis 4) A force of 250 N is exerted on a cable wrapped around a drum that has a diameter of 120 mm. What is the torque produced about the center of the drum? a) A. 15 N b) B. 30 N c) C. 45 N d) D. 60 N 5) A simple pendulum consists of a 3.0 kg point mass hanging at the end of a 2.0 m long light string that is connected to a pivot point. What is the magnitude of the torque (due to gravitational force) around this pivot point when the string makes a 5.0o angle with the vertical? a) A. 2.1 Nm b) B. 3.1 Nm c) C. 4.1 Nm d) D. 5.1 Nm 6) What torque is produce if you apply a longer lever arm to an object for it to rotate? a) A. less torque b) B. more torque c) C. less acceleration d) D. more acceleration 7) What torque will be produced if the force is applied parallel to the lever arm? a) A. cannot be determined b) B. maximum torque c) C. minimum torque d) D. zero 8) Two disks have the same mass but one has twice the diameter of the other. Which would be harder to start rotating? a) A. both disks have the same moment of inertia b) B. both disks have a greater moment of inertia c) C. the larger one has a greater moment of inertia d) D. the smaller one has a greater moment of inertia 9) Moment of inertia depends on the following, EXCEPT a) A. torque b) B. shape and size of the body c) C. position and orientation of the axis of rotation d) D. distribution of mass of the body about an axis of rotation 10) What is the magnitude of the torque by a 3.0 N force applied to a door at a perpendicular distance of 0.25 m from the hinge? a) A. 0.25 Nm b) B. 0.50 Nm c) C. 0.75 Nm d) D. 1.00 Nm 11) Which of the following tells whether the object is in equilibrium? a) A. the object is in motion b) B. the forces acting are not equal c) C. the object moving at a constant speed d) D. the net force is equal to zero 12) What type of forces will cause an object to rotate? a) A. concurrent forces b) B. equilibrant forces c) C. normal forces d) D. non-concurrent forces 13) How many radians are there in 60 revolutions? a) A. 0.49 rad b) B. 0.98 rad c) C. 2.5 rad d) D. 18.8 rad 14) How long will the helicopter blade turn through 200 radians if its angular velocity is 60 rad/s? a) A. 2 seconds b) B. 3.3 seconds c) C. 4 seconds d) D. 6 seconds 15) Bowling has a mass of 5.5 kg and a radius of 12.0 cm. It is released so that it rolls down the alley at a rate of 12 revs/s. Find the magnitude of its angular momentum. a) A. 0.76 kgm2/s b) B. 1.8 kgm2/s c) C. 4.1 kgm2/s d) D. 5.1 kgm2/s 16) 1. Which of the following tells whether the object is not in equilibrium? a) A. the object is at rest b) B. the object is in motion c) C. the forces are balanced d) D. the object is moving at a constant velocity 17) It is measured in radian (rad), which is dimensionless a) A. Angular acceleration b) B. Angular momentum c) C. Angular position d) D. Angular velocity 18) A baton twirler spins a baton at 25 RPM, what is its angular velocity in rad/s? a) A. 2.6 rad/s b) B. 4.71 rad/s c) C. 6.5 rad/s d) D. 10.5 rad/s 19) 4. A centrifuge rotates so that 0.25 m from the center is traveling at 343 m/s (the speed of sound). What is its angular velocity? a) A. 915 rad/s b) B. 1372 rad/s c) C. 1537 rad/s d) D. 2301 rad/s 20) A 7.0 kg solid ball with a radius of 10 cm is rolling at 10 m/s. Calculate the angular momentum of the ball. a) A. 1.8 kgm2/s b) B. 2.8 kgm2/s c) C. 3.8 kgm2/s d) D. 4.8 kgm2/s 21) Which of the following is the rotational equivalent of force? a) A. Angular momentum b) B. Angular velocity c) C. Moment of inertia d) D. Torque 22) It is the resistance of an object to change its state of rotational motion a) A. Angular momentum b) B. Angular velocity c) C. Moment of inertia d) D. Torque 23) Angular momentum depends on a) A. Angular velocity and acceleration b) B. Force and radius c) C. Mass and acceleration d) D. Moment of inertia and angular velocity 24) In an isolated system, the moment of inertia of a rotating object is halved. What happens to the angular velocity of the object? a) A. It remains the same b) B. It is quartered c) C. It is halved d) D. It is doubled 25) What happens to the angular velocity of the object? I start pushing a merry-go-round with a torque of 10 Nm. It has a moment of inertia of 100 kgm2. What is the rotational speed after 3 s, assuming it starts at rest? a) A. 0.3 s-1 b) B. 30 s=1 c) C. 30 s d) D. 3 s-1 26) Moment of inertia in rotational motion depends on a) A. Angular velocity and acceleration b) B. Force and radius c) C. Mass and radius d) D. Moment of inertia and angular velocity 27) It is the rate of change of angular momentum a) A. Angular acceleration b) B. Angular velocity c) C. Moment of inertia d) D. Torque 28) A figure skater goes into a spin, keeping her arm at her sides. Which is true might occur when she extends her arms? a) A. her angular velocity increases b) B. her angular momentum stays the same c) C. her rotational inertia decreases d) D. her angular velocity remains the same 29) If the angular momentum of the system of particles is constant, which of the following statements must be true? a) A. The net external torque on the system is constant. b) B. No torques are acting on any part of the system c) C. The net torque is zero on each part of the system d) D. The net torque is zero for the whole system 30) A 4.0 kg block travels around a 0.50 m radius circle with an angular velocity of 12 rad/s. What is its angular momentum about the center of the circle? a) A. 12 kgm/s2 b) B. 24 kgm/s2 c) C. 48 kgm/s2 d) D. 6 kgm/s2 31) 1. Which of the following statements best describes the law of universal gravitation a) A. Two objects pull on each other with a force that is proportional to the product of their masses and inversely proportional to the distance between b) product of their masses and inversely proportional to the distance between 32) If the distance between two objects is 2.5 meters and is increased to 5 meters, what happens to the gravitational force between them? a) A. it doubles  b) B. it decreases by a factor of 4 33) Which of the following statements describes Kepler’s first law? a) A. Planets move in elliptical orbits, with the Sun at one focus of the ellipse. b) B. An imaginary line between the Sun and a planet sweeps out equal areas in 34) What did Kepler say in his second law about the line connecting a planet to the sun? a) A. sweeps out different areas in equal time intervals b) B. sweeps out equal areas in equal time intervals c) C. sweeps out equal areas in different time intervals d) D. the velocity is constant no matter what size the orbit is 35) Which of Kepler’s laws of planetary motion explains a planet that is farther away from the sun travels the same amount of time as when it is closer to the sun due to equal areas? a) 1st law b) 2nd law 36) Which Kepler’s law stated that the ratio of the squares of the periods T of any two planets revolving around the sun is equal to the ratio of the cubes of their mean distance from the sun? a) 1st law b) 2nd law c) 3rd law 37) Knowing how long a planet takes to orbit the sun, helps scientists determine the distance that the planet is from the sun is explained in which Kepler’s law of planetary motion?   a) 1st law b) 2nd law c) 3rd law

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