Physics

posted by .

A spacecraft approaching the earth launches an exploration vehicle. After the launch, an observer on earth sees the spacecraft approaching at a speed of 0.74c and the exploration vehicle approaching at a speed of 0.98c. What is the speed of the exploration vehicle relative to the spaceship?

I keep getting .259 which is the wrong answer. I don't know what Im doing wrong I use the velocity addition formula but it never works. Please help!!

  • Physics -

    0.98c is the relative velocity of the probe with respect to the Earth (V3). That is the relativistic sum of the probe velocity (V2) with respect to the spaceship, and the spaceship with respect to Earth (V1).

    V3 = (V1 + V2)/[1 + (V1*V2)/c^2]

    You want to solve for V2.
    I get V2 = 0.873c

  • Physics -

    Thank you. i sort of had to back track to get the answer you got but eventually got it. Thank you!!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    A siren mounted on the roof of a firehouse emits sound at a frequency of 900 Hz. A steady wind is blowing with a speed of 15 m/s. Take the speed of sound in calm air to be 343 m/s. (c) Firefighters are approaching the siren from various …
  2. Physics

    When a spacecraft travels from the Earth to the Moon, both the Earth and the Moon exert a gravitational force on the spacecraft. Eventually, the spacecraft reaches a point where the Moon's gravitational attraction overcomes the Earth's …
  3. Math

    The radius of Earth is 3,959 miles. A spacecraft orbits 6 miles above the surface of Earth. The spacecraft completes 220° of a revolution around Earth in one day. What is the average speed of the spacecraft?
  4. Physics--please help!!

    A student in a parked car honks the horn, which has a `proper' frequency of 320 Hz. An observer in an approaching vehicle measures the frequency of the sound to be 355 Hz. Calculate the speed of the approaching vehicle. Use 340 m/s …
  5. physics

    Approaching a flashing pedestrian activated traffic light, a driver must slow down to a speed of 30km/h. If the cross walk is 150m away and the vehicle's initial speed us 59km/h, what must be the magnitude of the car's acceleration …
  6. physics

    A airplane is approaching you at a speed of 360km/h. If you measure the pitch of its approaching engines to be 512 Hz, what must be the actual frequency of the sound of the engines?
  7. physics

    An astronaut is traveling in a space vehicle moving at 0.520c relative to the Earth. The astronaut measures her pulse rate at 74.0 beats per minute. Signals generated by the astronaut's pulse are radioed to the Earth when the vehicle …
  8. physics

    The five engines of the first stage of a launch vehicle provide a total thrust of 31.5 x 106 newtons to the space vehicle (launch vehicle and spacecraft). Assuming the acceleration is uniform, calculate the acceleration of the 2.764 …
  9. modern physics

    Missiles are fired towards the earth from a spacecraft. The missiles are moving with a speed of 0.8c with respect to the spacecraft. If the spacecraft itself has a speed of 0.3c with respect to Earth, how fast are the missiles observed …
  10. modern physics

    Missiles are fired towards the earth from a spacecraft. The missiles are moving with a speed of 0.8c with respect to the spacecraft. If the spacecraft itself has a speed of 0.3c with respect to Earth, how fast are the missiles observed …

More Similar Questions