6) A rocket is moving at 0.7c. mz mssiles a) According to an observer on the rocket it launches a missile in the same direction it is moving with a speed of 0.4c. An observer on the ground measures the speed of the missile. What velocity does she measure? Please answer in terms of c. b) If the same rocket launched the same missile in a direction opposite to the motion of the rocket, what would the velocity seen from the observer on the ground be? What is its direction as seen from the ground? Hint: The addition of velocities requires a special formula which was in the lectures. To figure out how to use it start with the non-relativisitc version: V12 = V13 + V32 then modify it with the correct denominator to make it relativistic: V12 = (V13 + V32)/(1+(V13 V3/c°)). Pay careful attention to the signs of the velocities. If you end up with a speed larger than the speed of light you have made a mistake.

6) A rocket is moving at 0.7c. mz mssiles a) According to an observer on the rocket it launches a missile in the same direction it is moving with a speed of 0.4c. An observer on the ground measures the speed of the missile. What velocity does she measure? Please answer in terms of c. b) If the same rocket launched the same missile in a direction opposite to the motion of the rocket, what would the velocity seen from the observer on the ground be? What is its direction as seen from the ground? Hint: The addition of velocities requires a special formula which was in the lectures. To figure out how to use it start with the non-relativisitc version: V12 = V13 + V32 then modify it with the correct denominator to make it relativistic: V12 = (V13 + V32)/(1+(V13 V3/c°)). Pay careful attention to the signs of the velocities. If you end up with a speed larger than the speed of light you have made a mistake.