Aliens slowing down to observe Earth often are distracted by lighthouses. As aliens pass Earth in their spaceship they notice a lighthouse completes its circuit once every 8.0 s, however the lighthouse attendant has set the lighthouse to complete its circuit every 4.1 s from his point of view. How fast is the alien spaceship traveling in terms of the speed of light?

The value is

Explanation:

From the question we are told that

The time taken as seen by aliens

The time taken as seen by attendant

Generally from the dilation of time equation we have that

Here c is the speed of light

v is the speed of the alien ship

=>

=>

=>

=>

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.