What causes an electromagnet to create a magnetic field? A. The Earth's magnetic field.

B. The poles are attracted to each other.

C. The iron is wrapped with a coiled wire.

D. There is a current flowing through the wire.

Which lists the pairs of plates in order from least to greatest in terms of the work done to move the electron?

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

What is an aquifer for science class