IF YOU KNOW HOW TO DO ANY OF THEM PLEASE SHOW WORK AND STATE THE QUESTION NUMBER
ID: 1499128 • Letter: I
Question
IF YOU KNOW HOW TO DO ANY OF THEM PLEASE SHOW WORK AND STATE THE QUESTION NUMBER YOU'RE ANSWERING
1) At what speed would you have to move past a 7.16 cm ruler so that you would observe its length to be 3.58 cm? The speed of light is 3×108 m/s. (answer in units of c)
2) The starship Enterprise, passing the Earth at 0.9 c, sends a drone ship forward at 0.48 c relative to the Enterprise. What is the drone’s speed relative to the Earth? c is the speed of light. (Answer in units of c.)
3) (PART 1 of 2) The Sun radiates about 4 × 1026 J of energy into space each second. How much mass is released as radia- tion each second? The speed of light is 3 × 108 m/s. (answer in units of kg)
4) (PART 2 of 2) If the mass of the Sun is 2×1030 kg, how long can the Sun exist if the energy release continues at the present rate? (answer in unit of y)
Explanation / Answer
Answered q1 & q2 ----
(1)
Length of contraction is given by,
L = Lo * sqrt(1 - v^2/c^2)
3.58 = 7.16 * sqrt(1 - v^2/c^2)
v = c * sqrt(1 - (3.58/7.16)^2)
v = 0.866 c
(2)
v = 0.9 c
u = 0.48 c
Let drone’s speed relative to the Earth, Vde ?
Vde = (u + v)/( 1 + u*v/c^2
Vde = (0.9+0.48)/(1 + 0.9*0.48)
Vde = 0.964 c