Of these electromagnetic waves, which has the A Over a unit distance, wave A has three crests and two troughs. The wave begins and ends at the rest position. B Over a unit distance, wave B has two crests and one trough. The wave begins at the rest position and ends at the top of a crest. C Over a unit distance, wave C has four crests and four troughs. The wave begins and ends at the rest position. longest wavelength?

Wave B has the longest wavelength

Explanation:

The wavelength of a wave is the distance between two consecutive points that are in phase.

The wavelength of a wave is also defined as the distance between successive crests or troughs along the z-axis.

A crest is the point of maximum upward displacement whereas a trough is a point of maximum downward displacement.

Comparing the three waves A, B and C over a unit distance.

Wave A:

Wave A has three crests and two troughs. The wave begins and ends at the rest position. There are 2½ successive points in phase in wave A

Therefore, the wavelength = 1/2.5 = 0.4

Wave B:

Over a unit distance, wave B has two crests and one trough. The wave begins at the rest position and ends at the top of a crest. There are 1¼ successive points in phase in wave B

Therefore, the wavelength = 1/1¼ = 0.8

Wave C:

Over a unit distance, wave C has four crests and four troughs. The wave begins and ends at the rest position.

There are 4 successive points in phase in wave B

Therefore, the wavelength = 1/4 = 0.25

Therefore, wave B has longest wavelength

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

i think it would be 5