The spaceship Lilac, based on the Purple Planet, is 721 m long when measured at rest. When the Lilac passes Earth, observers there measure its length to be 661 m. At what speed v is the Lilac moving with respect to Earth? Express your answer as a multiple of the speed of light c.

The speed of Lilac is 0.399c.

Explanation:

The size of spaceship Lilac measured at the rest position = 721 m  

The length of  Lilac when it passes Earth = 661 m

Below is the calculation for speed at which Lilac is moving.

Here, L, is the length of spaceship when it passes the earth.

is the length of spaceship measured at rest.

V is the speed.

lol

explanation:

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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