SPH4U Short Answer 1. An object is moving such that its position-time graph and velocity-time graphs are both straight lines. The acceleration-time graph is a horizontal straight line. Formulate and present an argument why this should be the case. 2. At the end of a free-fall ride, the brakes kick in and decelerate the riders at 4g. What is the apparent weight of a 75.0 kg rider during braking? 3. A pendulum clock is manufactured at the north pole, and adjusted to keep correct time. It is sold to a customer who lives on the equator. Will the clock keep correct time on the equator? Explain your answer. 4. When two dynamics carts meet head-on, cushioned by a spring with spring constant, k, there is a point where the spring has maximum compression x. Solve the conservation of mechanical energy equation for x, 5. Xenia says, "The orbital speed of a satellite would remain unchanged if the central body's mass an radius were increased by the same factor k." Is she correct? Explain your answer. 6. Planetary orbits are not perfect circles, but rather ellipses. The Sun is not at the centre of the ellipse, but at a special point known as a focus, as shown. Describe the changes in speed of a planet as it makes one complete orbit. B Orbit Sun C Planet & A 7. One way of testing general relativity is gravitational lensing. Explain how this works, and what differences occur in the predictions of Newton and Einstein. 8. A current of 4.50 A flows through a wire 15.0 cm long. The wire is in a magnetic field of strength 120 AT at an angle of 75.0 to the wire. What is the magnitude of the magnetic force acting on the wire?9. Antimatter cannot be allowed to come into contact with ordinary matter, or the two will annihilate each other. One way of doing this is to "trap" the antimatter particle in a circular path in a magnetic field. Suppose that this is done with a positron, the antimatter counterpart of an electron, which has the same magnitude but opposite sign as the charge on the electron. The "magnetic bottle" trap has a maximum diameter of 5.00 cm, and the captured positron is moving at 8.92 x 10" mi's . What is the minimum strength of magnetic field required? 10. A student connects two loudspeakers to emit the same frequency of sound. She stands on the right bisector of the line connecting the speakers, and moves her head from the side to side. The sound gets louder as she moves off the right bisector. Are the speaker in phase or out of phase? Explain your answer. 11. A double-slit interference experiment is carried out with yellow light of wavelength 550 nm from a sodium vapour lamp. The slits are 0.00640 mm apart. What is the angle for the fifth order dark fringe? 12. Select a fact that you learned in this chapter that was of particular interest to you. Explain why you found it interesting. 13. Red light of wavelength 6. 20 x 10 ' m reflects from a soap bubble with an index of refraction of 1.35. What is the thickness of the film at the fifth order maximum? 14. Reflect on the concepts that you learned in this chapter. Select an example of a fact or concept that your found surprising, and how it changed your thinking. Use an example from your own life. 15. Calculate the de Broglie wavelength for a passenger jet with a mass of 3.22 X 10" kg travelling at 1024 km/h