Two rockets approach each other. Each is traveling at 0.61c in the earth's reference frame. Part A What is the speed, as a fraction of c, of one rocket relative to the other? ΜΕ ΑΣΦ ? 3 20 F3 % 85 54 $ E R Submit Request Answer Provide Feedback FR t 96 FB & 7 8 9 Y U D F G H J K M 0

(a) Use the distance and velocity data in Figure 3.64 to find the rate of expansion as a function of distance. (b) If you extrapolate back in time, how long ago would all of the galaxies have been at approximately the same position? The two parts of this problem give you some idea of how the Hubble constant for universal expansion and the time back to the Big Bang are determined, respectively. Figure 3.64 Five galaxies on a straight line, showing their distances and velocities relative to the Milky Way (MW) Galaxy. The distances are in millions of light years (Mly), where a light year is the distance light travels in one year. The velocities are nearly proportional to the distances. The sizes of the galaxies are greatly exaggerated; an average galaxy is about 0.1 MlY across.

(a) All but the closest galaxies are receding from our own Milky Way Galaxy. If a galaxy 12.0109ly ly away is receding from us at 0. 0.900c, at what velocity relative to us must we send an exploratory probe to approach the other galaxy at 0.990c, as measured from that galaxy? (b) How long will it take the probe to reach the other galaxy as measured from the Earth? You may assume that the velocity of the other galaxy remains constant. (c) How long will it then take for a radio signal to be beamed back? (All of this is possible in principle, but not practical.)

▾ Part A A starship voyages to a distant planet 10 ly away. The explorers stay 4.0 yr, return at the same speed, and arrive back on earth 26 yr after they left. Assume that the time needed to accelerate and decelerate is negligible. What is the speed of the starship? Express your answer using two significant figures. ΜΕ ΑΣΦ 20 Submit Request Answer Part B ? How much time has elapsed on the astronauts' chronometers? Express your answer using two significant figures. ΕΠΙ ΑΣΦ VAΣ ? t = Submit Request Answer years

Two electrons are brought close together, to a distance of 83 pm apart. They are then both released from rest, accelerating and travelling away from one another. When the two particles are very far apart, how fast will they be going, in m/s? You Ancu

the free-falling experiment is done on the moon stone dropped from height h=1m. after 1.1sec it hits the ground what is the gravity acceleration of the moon O a. 1.82m/s2 O b. 1.65m/s2 O c. 0.91 m/s2 O d. 3.3m/s2 O e. 2m/s2

A car is going 20m/s in 10sec. How far the car goes?   1. 2m   2. 0.5 m   3. 200m   4. 50.2 m

The distnace from earth to the moon is 239,000 miles. a. how many kilometers are in 239000 miles? b. given that the light travels at 3.00*10^8 m/s , how many minutes does it take for light to travel to the moon ? c. The apollo 10 mission holds the record for the highest speed by a manned vehicle at 11080 m/s . How many minutes would it take for the apollo 10 mission to reach the moon assuming the rocket travels ina straight line at that top speed? d. The apollo 11 mission took 73.45 hours to reach lunar orbit once it left earths orbit. The avergae speed duirng that time was 5500km/hr. How many miles did the apollo 11 mission actually travel in space ?

R3M.8 The new earth-Pluto shuttle shuttle line boasts that it can take you between the two planets (which are about 5.0 hours of distance apart) in 2.5 hours (according to a rider’s watch). Assume that acceleration and deceleration periods are very brief so that you spend essentially all the trip traveling at a constant velocity. a) What time interval must synchronized clocks in the solar system’s reference frame register between the shuttle’s departure from earth and its arrival at Pluto if the advertisement is true? b) What is the shuttle’s cruising speed?

An astronaut journeys to a nearby star for 2.5 years according to his clock. When he returns, he finds that 7.5 years have elapsed. What was his speed?    Choices: A. 0.2 c B. 0.45 c C. 0.94 c D. 1.54 c