A ladder 5.10 m long leans against a wall inside a spaceship. From the point of view of a person on the ship, the base of the ladder is 2.50 m from the wall, and the top of the ladder is 4.45 m above the floor. The spaceship moves past the Earth with a speed of 0.87c in a direction parallel to the floor of the ship. Find the angle the ladder makes with the floor, as seen by an observer on Earth.

Respuesta :

Answer:

The angle made by the ladder on the floor, [tex]\theta = 74.52^{\circ}[/tex]

Given:

Length of the ladder, l = 5.10 m

Base of the ladder from the wall, [tex]L_{o} = 2.50 m[/tex]

Top of the ladder, [tex]H_{o} = 4.45 m[/tex]

Speed of the spaceship, [tex]v_{s} =  0.87c[/tex]

Explanation:

Now, using the formula for length contraction from Einstein's theory of relativity:

[tex]L = L_{o}\sqrt{\frac{1 - v_{s}^{2}}{c^{2}}}[/tex]

where

c = speed of light in vacuum

From the above relation for length contraction:

[tex]L = 2.5\sqrt{\frac{1 - (0.87c)^{2}}{c^{2}}}[/tex]

L = 1.233 m

Now, the angle made by the ladder on the floor:

[tex]tan\theta = \frac{H_{o}}{L}[/tex]

[tex]\theta = tan^{- 1}\frac{4.45}{1.233}[/tex]

[tex]\theta = 74.52^{\circ}[/tex]