An experiment is conducted to determine how the arm length of a pendulum affects its period. The experimental design calls for varying the length of the arm and the mass of the bob. Which is true about this experiment, based on good experimental design?

A.) Only the mass should be changed. The arm length should remain the same.

B.) The force applied to the mass should be varied for each trial.

C.) Only the arm length should be changed. The mass should remain the same.

D.) The material the arm is made of should be varied for each trial.

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

the moon affects the earth gravitation ally, causing certain motions of that body and also producing tides in its ocean and atmosphere. the tidal wave in our atmosphere is, however, far too minute to be an effective cause in any known meteorological phenomenon.

explanation: