1. An object moves at constant speed in a circular path. Which of the following statements are true? Select two answers. (A) The velocity is changing. (B) The velocity is constant. (C) The magnitude of acceleration is constant. (D) The magnitude of acceleration is changing. Questions 2-3 refer to the situation below. A 60 cm rope is tied to the handle of a bucket which is then whirled in a vertical circle. The mass of the bucket is 3 kg. 2. At the lowest point in its path, the tension in the rope is 50 N. What is the speed of the bucket? (A) 1 m/s (B) 2 m/s (C) 3 m/s (D) 4 m/s 3. What is the critical speed below which the rope would become slack when the bucket reaches the highest point in the circle? (A) 0.6 m/s (B) 1.8 m/s (C) 2.4 m/s (D) 4.8 m/sAn object moves at a constant speed in a circular path of radius r at a rate of 1 resolution per second. What is its acceleration? (A) o (B) 23t2r (C) 2n2r2 (D) 4H2? In an effort to tighten a bolt, a force F is applied as shown in the figure above. If the distance from the end of the wrench to the center of the bolt is 20 cm and F = 20 N, what is the magnitude of the torque produced by F? (A) 1 N.m (B) 2 N.m (C) 4 N.m (D) 10 N.m suspension point 60 mIn the figure above, what is the torque about the pendulum's suspension point produced by the weight of the bob, given that the length of the pendulum, L, is 80 cm and m = 0.50 kg ? (A) 0.5 N.m (B) 1.0 N.m (C) 1.7 N.m (D) 2.0 N.m M A uniform meter stick of mass 1 kg is hanging from a thread attached at the stick's midpoint. One block of mass m = 3 kg hangs from the left end of the stick, and another block, of unknown mass M, hangs below the 80 cm mark on the meter stick. If the stick remains at rest in the horizontal position shown above, what is M? (A) 4 kg (B) 5kg (C) 6 kg (D) 8 kgIf the distance between two point particles is doubled, then the gravitational force between them (A) decreases by a factor of 4 (B) decreases by a factor of 2 (C) increases by a factor of a (D) increases by a factor of 4 At the surface of Earth, an object of mass art has weight m. If this object is transported to an altitude that is twice the radius of Earth, then at the new location, (A) its mass is m and its weight is Lia/2 (B) its mass is art/2 and its weight is iii/4 (C) its mass is m and its weight is tom (D) its mass is m and its weight is wig A moon of mass m orbits a planet of mass loom. Let the strength of the gravitational force exerted by the planet on the moon be denoted by F1, and let the strength of the gravitational force exerted by the moon on the planet be F2. Which of the following is true? (A) F, = tooJF'2 (13)}?1 = toF2 (C) F, = F, (D) F2 2 lo}?1 The dwarf planet Pluto has 1/500 the mass and 1/ 15 the radius of Earth. What is the value of g (in III/'52] on the surface of Pluto? (A) E 225 (a) E 15 (C) E 50 (n) E 50 A satellite is currently orbiting Earth in a circular orbit of radius R; its kinetic energy is K1. If the satellite is moved and enters a new circular orbit of radius 2R, what will be its kinetic energy? [A] i 4 (B) i 2 (C) 2K1 (D) 4K1 A moon of Jupiter has a nearly circular orbit of radius R and an orbit period of T. Which of the following expressions gives the mass of Jupiter? (A) 4112}? T2 [B] 2:133 (GT2) (C) i (GT ) (D) 41:15:} (GT1) Two large bodies, Body A of mass m and Body B of mass 4m, are separated by a distance R. At what distance from Body A, along the line joining the bodies, would the gravitational force on an object be equal to zero? [Ignore the presence of any other bodies.) (A) E 16 (B) E 8 (C) E 4 (D) E 3 You are looking at a top view of a planet orbiting the Sun in a clockwise direction. Which of the following would describe the velocity, acceleration, and force acting on the planet due to the Sun's pull at point P ? (AJUL HT FT (ijl :14 F (DJUT {14 F4 Which of the following statements are true for a satellite in outer space orbiting the Earth in uniform circular motion? Select two answers. (A) There are no forces acting on the satellite. (B) The force of gravity is the only force acting on the satellite. (C) The force of gravity is balanced by outward force of the object. [DJ The mass of the satellite has no effect on the orbital speed. An object of mass m is traveling at constant speed v in a circular path of radius r. How much work is done by the centripetal force during one-half of a revolution? (A) JMU2 (B) o (C) amver (D) 2mv2rA robot probe lands on a new, uncharted planet. It has determined the diameter of the planet to be 8 x 10'5 In. It weighs a standard 1 kg mass and determines that 1 kg weighs only 5 newtons on this new planet. :a) What must the mass of the planet be? b) What is the acceleration due to gravity on this planet? Express your answer in both m/s2 and g's (where 1 g = 10 m/sg). :c) What is the average density of this planet? The Earth has a mass of 6 x 1024 kg and orbits the Sun in 3.15 x 107 seconds at a constant radius of 1.5 x 1011 m. :a) What is the Earth's centripetal acceleration around the Sun? :b) What is the gravitational force acting between the Sun and Earth? :c) What is the mass of the Sun? .An amusement park ride consists of a large cylinder that rotates around its central axis as the passengers stand against the inner wall of the cylinder. Once the passengers are moving at a certain speed, 1), the oor on which they are standing is lowered. Each passenger feels pinned against the wall of the cylinder as it rotates. Let r be the inner radius of the cylinder. Ia) Draw and label all the forces acting on a passenger of mass m as the cylinder rotates with the oor lowered. :b) Describe what conditions must hold to keep the passengers from sliding down the wall of the cylinder. Cc) Compare the conditions discussed in part (b) for an adult passenger of mass m and a child passenger of mass m / 2. . A curved section of a highway has a radius of curvature of r. The coefficient of friction between standard automobile tires and the surface of the highway is #5. (a) Draw and label all the forces acting on a car of mass m traveling along this curved part of the highway. Eb) Compute the maximum speed with which a car of mass m could make it around the turn without skidding in terms of .115, r, g, and m. City engineers are planning to bank this curved section of highway at an angle of 9 to the horizontal. (c) Draw and label all of the forces acting on a car of mass m traveling along this banked turn. Do not include friction. [d) The engineers want to be sure that a car of mass m traveling at a constant speed 1) (the posted speed limit) could make it safely around the banked turn even if the road were covered with ice (that is, essentially frictionless). Compute this banking angle 9 in terms of r, u, g, and m