# Physics

posted by .

Astrotrain, a Decepicon triple changer, is traveling at a speed of .77c towards Earth, as seen by Blaster, who is on Earth inside Fortress Maximus. Astrotrain's computers tell him the icon rocket was fired at .35c. Determine the length of the ion rocket as seen by Blaster and Fortress Maximus.

• Physics -

Um, how can one determine a relativistically affected length, if no length at all is given in the problem?

• Physics -

I apoligize. I forgot to include that Astrotrain fired a 3m ion rocket at Fotress Maximus.

• Physics -

The speed of the rocket relative to Earth must first be computed. There is a relavistic velocity-addition formula for that. You can find it at
The value for the relative velocity is
v = (.77c + 0.35c)/[1 + (0.77*0.35)]
= 0.882 c
Now use the Fitz-Gerald contraction formula for the apparent length of the rocket, L', as seen from Earth
L' = L * sqrt[1 - (v/c)^2]= 0.471 L
= 1.41 m

## Similar Questions

1. ### Physics

Take into account the Earth's rotational speed (1 rev/day) and determine the necessary speed, with respect to the Earth, for a rocket to escape if fired from the Earth at the equator in a direction a) eastward; b) westward; c) vertically …
2. ### Physics

Take into account the Earth's rotational speed (1 rev/day) and determine the necessary speed, with respect to the Earth, for a rocket to escape if fired from the Earth at the equator in a direction a) eastward; b) westward; c) vertically …
3. ### physics entry

A meteor headed straight towards the earth has an approach speed of 2.00e3 m/s at a distance of 7 earth radii from the center of the earth. What will be its speed when it reaches earth a 6.38e6 m(ignore the effects of atmosphere)?
4. ### physics

A rocket is fired straight up through the atmosphere from the South Pole, burning out at an altitude of 208 km when traveling at 5.8 km/s. (a) What maximum distance from Earth's surface does it travel before falling back to Earth?
5. ### physics

A rocket is fired straight up through the atmosphere from the South Pole, burning out at an altitude of 208 km when traveling at 5.8 km/s. (a) What maximum distance from Earth's surface does it travel before falling back to Earth?
6. ### Physics

A rocket cruising past Earth at 0.79c shoots two bullets at 0.92c relative to the rocket with one of the bullets fired along the direction of the rocket's motion and the other fired opposite the rocket's motion. (a) What velocity does …
7. ### Physics

A rocket starts from rest and moves upward from the surface of the earth. For the first 10s of its motion, the vertical acceleration of the rocket is given by a_y =( 2.70m/s^3)t, where the +y-direction is upward. 1) What is the height …
8. ### Physics

A comet is traveling towards the earth. The comet has a mass of 5.50E+12 kg and a radius of 323 m. The comet is traveling with a speed of 13.5 km/s and spinning with a period of 0.15 seconds when its center is a distance 2.28E+7 m …
9. ### Physics

Take into account the Earth's rotational speed (1 rev/day) and use 5 significant figures. (a) Determine the necessary speed, with respect to Earth, for a rocket to escape if fired from the Earth at the equator in a direction eastward. …
10. ### Physics

A rocket that weighs 7840 N on earth is fired. The force of propulsion is + 10 440N. Determine a) the mass of the rocket, b) the acceleration of the rocket, c) the velocity of the rocket at the end of 8.0 s.

More Similar Questions