- #1

Caneholder123

- 10

- 0

**1. A distant camera is taking an image of a bullet of proper length [itex]l_0[/itex] and velocity [itex]v[/itex]. The bullet is moving on a straight line which is parallel to the ruler (a bit behind the bullet, when it is watched from the camera). An angle between the velocity vector and the line that connects the camera with the bullet is [itex]\beta[/itex]. Determine the length of the bullet as seen from the camera, i.e. how much of the ruler is hidden.**

## Homework Equations

Lorentz transformations, from which the formula for the length contraction follows:

[tex]l=\frac {l_0}{\gamma}[/tex]

## The Attempt at a Solution

I just don't get this problem. Why is the angle [itex]\beta[/itex] given? Under the assumptions that the camera is far from the bullet and that the bullet is close to the ruler, isn't the length of the bullet measured just the contracted length? Angle [itex]\beta[/itex] will be changed, but I just can't see where it goes in this story.