A spacecraft built in the shape of a sphere moves past an observer on the Earth with a speed of 0.500c. What shape does the observer measure for the spacecraft as it goes by?

Given the speed of the 0.500c, the spacecraft is spherical.

Explanation:

The length of an object is contracted in the direction of the motion. It can be visualize that if a spherical body is contracted along a particular axial direction then the shape of the spherical body is seem to be in shape of a pillow, similarly the spherical spacecraft moves away and seems to be contracted along the direction of motion, so it becomes a round shape flattened along the direction of motion.

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.