Question1

At rest, a light source emits 532 nm light.

(a) As it moves along a line connecting it and Earth, observers on Earth measure the wavelength to be 412 nm. What is the sources velocity and direction? 

(b)Was it to move in opposite direction at the same speed, what wavelength would be seen?

(c)Was it to circle earth at the similar speed what wavelength would be seen?

Question2

A cube of ice is taken from the freezer at -5.5and placed in a 110 aluminium calorimeter filled with 305 of water at room temperature of 20.0. The last situation is observed to be all water at 15.0. What was the mass of cube?

Question3

The discovery of a star orbiting the center of our galaxy with a 15-year period has led to the result that mass of the giant black hole at the center of our galaxy is about 3 million times that of the Sun. with ratios; compute the semi major axis of the star’s orbit. Translate the answer to light-years.