Air is cooled and
becomes denser.
Denser air sinks.
The process repeats, producing a (i wasn't sure about this one)
Air is heated and becomes less dense.
Less dense air rises.
hope this helps!
You can tell if vector is an unit because it has something to do with taking the magnitude of the vector.
also has a length 1. thus you should use pythagoras to check.
Hope this help
Answer:
a)
, b)
, c) 
Explanation:
a) The linear acceleration of the watermelon seed is:

![a_{r} = \left[\left(33\,\frac{rev}{min} \right)\cdot \left(2\pi\,\frac{rad}{rev} \right)\cdot \left(\frac{1}{60}\,\frac{min}{s} \right)\right]^{2}\cdot (0.023\,m)](https://tex.z-dn.net/?f=a_%7Br%7D%20%3D%20%5Cleft%5B%5Cleft%2833%5C%2C%5Cfrac%7Brev%7D%7Bmin%7D%20%5Cright%29%5Ccdot%20%5Cleft%282%5Cpi%5C%2C%5Cfrac%7Brad%7D%7Brev%7D%20%5Cright%29%5Ccdot%20%5Cleft%28%5Cfrac%7B1%7D%7B60%7D%5C%2C%5Cfrac%7Bmin%7D%7Bs%7D%20%5Cright%29%5Cright%5D%5E%7B2%7D%5Ccdot%20%280.023%5C%2Cm%29)

b) The watermelon seed is experimenting a centrifugal acceleration. The coefficient of static friction between the seed and the turntable is calculated by the Newton's Laws:





c) Angular acceleration experimented by the turntable is:



The tangential acceleration experimented by the watermelon seed is:


The linear acceleration experimented by the watermelon seed is:



The minimum coefficient of static friction is:


Answer:
0.0025 sec
Explanation:
Period = 1 / frequency = 1/400 = 0.0025 sec