Question

What is the wavelength light coming out from a tungsten bulb at

MULTIPLE CHOICE QUESTIONS (Each question in this section carries 2 marks). Attempt ALL questions from this section 1. A on e meter rod is moving along its length with a velocity of 0.6c. What is the length of the rod appears to an observer on the earth? a. 0.8m b. 0.9m c. 1.0m d. 1.8m Answer: An earthworm has eight hearts located at different parts of its body. The eight hearts must all beat at the same time in order to produce effective blood circulation. If an earthworm flies past us in a rocket ship travelling at the speed of light, it front hearts will be out of synch with its rear hearts. Nevertheless, the earth worm remains alive because a. The worm is so short that it no longer requires effective blood circulation. b. The worm is not perfectly rigid. c. The hearts remain synchronized in the worm's own frame. d. Both the heart beats and the respiration rate slows down Answer: James travels at high speed from the Earth to the star Alpha Centauri, four light years away. In James's frame a. The trip takes more time than it does in the Earth's frame. b. James travels to Alpha Centauri over a length that is shorter than four light years. c. Clocks on Earth and on Alpha Centauri are synchronized d. Alpha Centauri travels to James over a length that is shorter than four light years. 3. Answer: A train is 200 feet long in its own frame, and a railroad platform is 160 feet long in its own frame. The train rushes past the platform so fast that, in the platform's frame, the train and platform are the same length. How fast was the train moving? 4. a. (4/5)c b. (5/4)c с. (35)c d. (4/3)c Answer: 5. A spacecraftis moving relative to the earth. An observer on the earth finds that, betwen 1 pm and 2 pm according to her clock, 3601 s elapse on the spacecraft's clock. What is the spacecraft's speed relative to the earth? a. 7.1 x 10 m/s

Answer 1

appears length (L) = L.squareroot 1-v^2/c^2 epsilon L = 1m times squareroot 1-(0.66)^2/c^2 epsilon L = 1m times squareroot 1- 0.36c^2/c^2 epsilon L = 1m times squareroot 0.64 epsilon L = 0.8m +