A rocket fires a projectile at a speed of 0.95c while traveling past the earth. An earthbound scientist measures the projectile’s speed to be 0.90c. What was the rocket’s speed as a fraction of c?

Short Answer

Expert verified

The speed of rocket is 0.34 c.

Step by step solution

01

Given information

We have given that, a rocket fires a projectile at a speed of 0.95c while traveling past the earth. An earthbound scientist measures the projectile’s speed to be 0.90c.

02

Step 1.

Let the earth’s frame of reference is S and the rocket’s frame of reference is S ′. Speed of projectile while passing earth u = 0.95 c and speed of projectile observed by scientist in earth's frame of reference u' = 0.90 c.

03

Step 2. 

Using Lorentz velocity transformation equation to calculate the speed of rocket :

v=u-u'1-uu'c2

v=0.90c-0.95c1-(0.90c)(0.95c)c2

v=0.34c.

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Most popular questions from this chapter

Teenagers Sam and Tom are playing chicken in their rockets. As FIGURE Q36.2 shows, an experimenter on earth sees that each is traveling at 0.95cas he approaches the other. Sam fires a laser beam toward Tom.

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Hint: See the comment following Equation 36.22.

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