Tier 1

Question 1

Magnetic flux density

Answer 1

The force acting per unit current per unit length on a wire carrying a current that is normal to the magnetic field.

Question 2

Faraday’s Law of Electromagnetic Induction

Answer 2

The induced electromotive force is directly proportional to the rate of change of magnetic flux linkage.

Question 3

Diffraction

Answer 3

The spreading of a wave into the geometric shadow when it passes through a slit or past on edge of an obstacle.

Question 4

Coherent

Answer 4

When two waves are coherent, there is a constant phase difference between the waves.

Question 5

Electric field strength

Answer 5

The electric force per unit positive charge acting on a small stationary test charge at that point in the field.

Question 6

Electric potential

Answer 6

Work done per unit positive charge in moving a small positive test charge from infinity to that point.

Question 7

Gravitational field strength

Answer 7

Gravitational force of attraction per unit mass acting on a small test mass placed at that point in the field.

Question 8

Gravitational field potential

Answer 8

Work done per unit mass in bringing on a small test mass placed at that point in the field.

Question 9

Stationary wave formation

Answer 9

A stationary wave is formed when two waves of the same type, same amplitude, same frequency,wavelength and speed, travelling in opposite directions towards each other, meet and overlap to superpose across a length.