Afeynman clock consists of two perfectly reflecting plan parallel mirrors which are separated by a fixed distance, which face each other, and between which a very short pulse of light is reflected back and forth. the time between successive reflection of the pulse at one of the mirrors is the unit of time for an observer at rest relative to the mirrors. figure 1 is a diagram of a feynman clock as seen in the a-frame, relative to which the clock is at rest. the diagram shows the world line of a fixed point on each of the mirrors and the world line of a light signal which is reflected from the lower mirror at event e0, which strike the upper mirror at event e1, and which is reflected again from the lower mirror e2. the light signal travels along the x-axis. the time interval between two successive reflections from the lower mirror is δta, and the distance between the mirrors is δxa. (a) construct a loedel diagram from fig. 1 in which the b-frame moves backward along the xa-axis a speed v of about 0.5c. (b) show that the time interval between e0 and e2 in frame b is given by the time dilation formula δtb = δta * 1 / √(1-(v/c)^2) (c) show that the b-time interval δt1b between e0 and e1 and the interval δt2b between e1 and e2 are related to the corresponding a-time interval by δt1bδt2b = δt1aδt2a. (15%)

19. explain why a magnet from your refrigerator could not be used to lift something as heavy as a car. (chapter 7 – pages 202-203) 20. can a magnet ever have a single pole? explain your answer. (chapter 7 – page 208) 21. what happens to the wavelength of a wave if the frequency is increased? (chapter 9 – pages 280-281) 22. an ocean wave has a wavelength of 10 m and a frequency of 4.0 hz. what is the velocity of the wave? show the appropriate equation from your book and show your work with units. (chapter 9 – page 282) 23. as you sit outside, the sound of a siren becomes lower in pitch. is the emergency vehicle moving away from or towards you? explain how you know. (chapter 10 – page 315-316) 24. why are two astronauts in space unable to hear one another? (chapter 10 – page 307) 25. explain in at least 3 sentences how electromagnetic waves form. (chapter 11 – page 338-339) 26. using the chart on page 345 in your textbook, what are the three types of electromagnetic wave with wavelengths shorter than those of visible light. give an example of each. (chapter 11 – pages 345-351) 27. explain why a leaf usually appears to be green, but a rose typically appears red. (chapter 12 – page 373) 28. what is the difference in light that is refracted compared to light that is reflected? think in terms of speed of light as well as what happens to light waves when they interact with a medium. (chapter 12 – pages 369-370) 29. how are concave and convex lenses different? (chapter 13 – page 408-410) 30. what type of mirror is used in rearview mirrors in cars? why is it important that these mirrors have the warning, “objects in mirror are closer than they appear.”? (chapter 13 – page 405)

What is the scientific definition of energy that relates to work

How does the kinetic energy of a charge change as the charge moves under the effect of an electric field from higher potential to lower potential? a.the kinetic energy increases.b.the kinetic energy decreases.c.the kinetic energy remains the same.d.the kinetic energy is always zero.