Question 8 of 15 Which of the following distinguishes electromagnetic waves from mechanical
waves?
A. They carry energy.
B. They have frequencies.
C. They have wavelengths.
D. They don't require a medium to travel through.

Athin plate moves between two parallel, horizontal, stationary flat surfaces at a constant velocity of v = 7.5 m/s. the two stationary surfaces are spaced 4 cm apart, and the medium between them is filled with oil whose viscosity is 0.9 n·s/m2. the part of the plate immersed in oil at any given time is 2 m long and 0.5 m wide. if the plate moves through the mid-plane between the surfaces, determine the force required to maintain this motion. what would your response be if the plate was 1 cm from the bottom surface (h2) and 3 cm from the top surface (h1)? if the plate moves through the mid-plane between the surfaces, the force required to maintain the motion will be n. if the plate was 1 cm from the bottom surface (h2) and 3 cm from the top (h1) surface, the force required to maintain the motion would be n.

The period of a pendulum varies directly as the square root of the length of the pendulum and inversely as the square root of the acceleration due to gravity. find the period when the length is 144 cm and the acceleration due to gravity is 980 cm per second squared, if the period is 7pi seconds when the length is 289 cm and the acceleration due to gravity is 980 cm per second squared.

Atriangle with equal sides of length 10 cm has -2.5-nc charged objects at each corner. part a determine the direction of the electrical force exerted on the object at the top corner due to the two objects at the horizontal base of the triangle. determine the direction of the electrical force exerted on the object at the top corner due to the two objects at the horizontal base of the triangle. horizontally rightward vertically downward vertically upward horizontally leftward