If a star 100 light years from earth is beginning to expand into a giant star how long will it take for astronomers to observe this development explain

Point charges q1 = 51 µc and q2 = −27 µc are placed 1.0 m apart, with q2 on the right. what is the force (in n) on a third charge q3 = 19 µc placed midway between q1 and q2? (assume the positive direction is to the right. indicate the direction with the sign of your answer.)

Aloop of wire is in a magnetic field such that its axis is parallel with the field direction. which of the following would result in an induced emf in the loop? choose all that apply. a loop of wire is in a magnetic field such that its axis is parallel with the field direction. which of the following would result in an induced emf in the loop? choose all that apply. moving the loop outside of the magnetic field region. spin the loop such that its axis does not consistently line up with the magnetic field direction. change the magnitude of the magnetic field. change the diameter of the loop

Which of the following will cause an induced current in a coil of wire? the constant field of the earth passing through the coil a magnet resting near the coil a magnet being moved into or out of the coil a wire carrying a constant current near the coil