What would be the percent decrease in length of a 68.2-mm-long spacecraft traveling at that speed as seen from Earth

Aray diagram for a refracted light day is shown. what does the dashed line represent

How are calculation for velocity and speed different

Avery long solenoid of inner radius 2.75 cm creates an oscillating magnetic field of the form = for this solenoid, =0.00425 t and =319 rad/s. (a)what is the maximum value of the induced electric field at a perpendicular distance 1.45 cm from the axis of the solenoid? (b) what is the maximum value of the inducted electric field at a point 5.85 cm perpendicular from the axis of the solenoid?