Question 15 (1 point) Two twins leave Earth at the same time in two different space ships. Jeremy travels twice as fast as Marnie. What will happen to them after they travel for one year of time back on Earth? Q They will age by the same amount. 0 Jeremy will age more than Marnie. O Marnie will age more than Jeremy. 0 There is no way of knowing. Their ages will depend on the momentum of the spacecrafts. Question 16 (1 point) Two objects in motion have the same kinetic energy. The velocity of one object is half the velocity of the other. What is the ratio of their masses? (T) Question 17 (1 point) Two planets are far from any other bodies. If the distance between them is doubled, what happens to the gravitational force between them? Q It is doubled. Q It increases by a factor of 4. Q It is reduced by half. 0 It decreases by a factor of 4. Question 18 (1 point) Under what circumstances will the magnetic force acting on a proton in a magnetic field equal zero? 0 The field is parallel to the motion of the proton. O The proton is at rest with respect to the field. 0 The angle between the field lines and the motion of the proton is. 0 All of these. Question 19 (3 points) Consider the quantities displacement, velocity, change in velocity, acceleration, and jerk. Describe how these quantities can be determined from positiontime graphs, velocitytime graphs, and acceleration- tirne graphs. (C/3) Question 14 (1 point) Three identical objects are thrown from the same height through a window at the same time. Object A is thrown horizontally at 4.0 m/s, object B is thrown horizontally at 8.0 m/s, and object C is simply dropped. If air resistance is negligible, which object will reach the ground first? (T) O object A 0 object B 0 object C 0 objects B and C will land first and together 0 all three will land at the same time