<span>When an object travels in a curved path, there must be a force acting toward the center of the circular trajectory. This force is called "centripetal force", and it cause an acceleration of the object, called "centripetal acceleration". The effect of this acceleration is that the velocity of the object changes in direction: however if the circular motion is uniform, the speed (=the magnitude of the velocity) does not change. In this case, the magnitude of the centripetal force is given by
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where m is the mass of the object, v its velocity, and r the radius of the circular path.</span>
Answer:
thats a lot, which one u want me to do?
Explanation:
Answer:
The unit is the barn, which is equal to 10-28 m^2 or 10-24 cm^2
Explanation:
The standard unit for measuring a nuclear cross section (denoted as σ)
The whole definition of frequency is: <em>How often something happens. </em>
Especially referring to something that happens over and over and over and over.
One example is Choice-C: How often the particles of a medium vibrate.
"Frequency" comes from the word "frequent". That means "often", and "frequency" just means "often-ness" ... HOW often the thing happens.
Some other examples:
Frequency of jump-roping . . . maybe 60 per minute .
Frequency of rain . . . maybe 5 per month .
Frequency of an AM radio station . . . maybe 1 million waves per second.
(If it's something <u><em>per second</em></u>, then we call it "Hertz". That's not for the car rental company. It's for Heinrich Hertz, the German Physicist who was the first one to prove that electromagnetic waves exist. He sent radio waves all the way ACROSS HIS LABORATORY and detected them at the other side ( ! ), in 1887.)
Frequency of the wiggles in the sound wave coming out of a trumpet playing the note ' A ' . . . 440 Hertz.
Frequency of sunrise and the Chicago Tribune newspaper . . . 1 per day
Frequency of the cycle of Moon phases and an average human woman's ovulation cycle: 1 per 29.531 days, 1 per ~28 days .