Earth observes a rocket move away at 0.370c. The rocket is ...

[09madisonrousseau09]

Earth observes a rocket move away at 0.370c. The rocket is designed to launch a projectile at 0.505c relative to the rocket.
 
  (a) Fired straight ahead, what is the projectile speed observed from Earth?
  (b) Launched to the rear, what is the projectile speed observed from Earth?

Question 2

What is the energy of a photon of wavelength 3 cm?
 
  A) 82 eV
  B) 4.1  10-5 eV
  C) 41 eV
  D) 4.1  10-5 J
  E) 3 ergs

[Tabitha_2016]

Answer to Question 1

(a) 0.737c
(b) 0.166c

Answer to Question 2

B

[09madisonrousseau09]

Thanks for the timely response, appreciate it

[yeungji]

Gracias!