Santa

Is anyone good at astronomy? Hey guys, I recently took a test in Astronomy and we have a take home part of which we are allowed to do any research on the internet or any outside source to ascertain the information. Now given that I'm not too good at this class, any assistance would be greatly helpful. If you could explain why the answer is correct, that would be great and extremely helpful. The exam was rather hard, so any explanations would be great. 1.) The age of the universe can be deduced from a.)hubble law b).murphy's law c).keplers third law d.)inverse square law e.)shapley's law 2.) The age of the universe is close to a.)15 million years b.)15 billion years c.)completely unknown 3.) If you add mass to a black hole, its schwarschild radius a.) would decrease b.) would increase c.)does not change d.)would change its size unpredictably 4.)Sue sees andy fly by her space station at 99.9% of speed of light (y=20). If andy's spaceship was 20 meters long when measured while docked at the space port, what is its length when sue sees it as it passes by her? a.)1 meter 2.) 2 meters 3.) 10 meters d.)20 meters e.) 99.9 meters 5.) Andy's ship is flying at 99.9% of speed of light (y=20). If the star Vega is 20 light years away, how long will it take andy to travel there? (by the way the y is suppose to represent the greek symbol) a.) 1 year b.) 2 years c.) 10 years d.)20 years 6.) andy flys at 99.9% of speed of light (y=20) to the star vega and returns. How much older would andy's twin sister sue be when he returns? a.) 1 yr older b.)2 yrs older c.) 10 yrs older d.) 20 yrs older e.)38 yrs older 7.) What evidence leads astronomers to believe that they have detected black holes? a.) tiny dark spots drifting across faces of some distance stars b.)they have detected pulses of uv radiation coming from dark regions of space c.)x-rays from accretion disks orbiting dark massive objects d.)they have looked into a black hole with x-ray radar telescopes 7.) One way astronomers deduce that the Milky Way is a disk is that they a.)see stars arranged in a circular region around the north celestial pole b.)see far more stars along the band of the milky way than in other directions c.)see a large dark circle silhouette against the milky way in the southern hemisphere d.) see the same number of stars in all directions in the sky 8.) Suppose you observe a galaxy with a recession velocity of 2,000 km/sec, If hubble's constant is 100 km/sec per Mpc, what is the distance to the galaxy in mpc? a.)10 mpc b.)20 mpc c.)40 mps d.)100 mpc e.)200 mps 9.)Seeing your martian nemesis off in the distance across relatively empty interstellar space, you fire your first shot. Your nemesis is coming towards you at a speed of 0.5 times the speed of light (as measured by the folks watching anxiously on earth) and you are rushing towards him at 0.75 times the speed of light (again as measured by the folks watching from earth). At what speed does he see the photons from your laser cannon approaching him? a.) at c, the speed of light b.)at 1.25 c. c.) at 1.75c d.) at 2.25c 10.) At what speed does your nemesis see you coming towards him? a.)at 0.25c b.)at 0.5c c.) at 0.75c d.) at 1.25c e.) slower than c but faster than 1/2c 11.) If, as measured by a clock on eaerth, the battle lasts for exactly 8 minutes, how long does the blattle last to you if you maintain your high velocity throughout the entire time? a.) exactly 8 minutes b.) shorter than 8 minutes c.) longer than 8 minutes d.)the battle will seem to last forever Thank you guys! Much appreciated First off, this isn't cheating. We're actually allowed to do this as instructed by the professor. He said we can ask anyone we want these question except the TA's. I'm glad you guys took the time to help me out. Don't get why you waste your time even responding if it offends you that much. Like I said, this is the take home portion and we are allowed to ask whoever and do as we please to find the information out. And for those wondering, I did try out each and every question. The test consisted of 43 but these were the ones I had most difficulty with. I did research on Google and got some of them but the math ones proved to be quite difficult. Sorry for not posting the answers I originally had. I know I flunked the test so it seemed rather senseless.