Answer:
A, and D are the answers
Explanation:
The pulley. It is located where the bicycle chain and gears are. The chain is wrapped around the pulley which turns and causes the wheel to turn on its axle.
Answer: Wave speed= frequency x wavelength
=20 x 3
=60 m/s
Explanation:
If they both are moving with the same speed and direction
i.e. covering the same distance in the same time interval in the same direction
Think of it like this, gravity has to pull harder on the heavier object to make them fall at the same rate , but doesn't have to pull as hard for the lighter object , thus is why sometimes heavier objects fall faster then lighter ones
Beat frequency, fb = |f2-f1|
That is, beat frequency is the absolute difference between two frequencies. Is is as a results of destructive and constructive inferences.
Therefore, in this case:
fb = 203 - 199 = 4 Hz