Explain what circadian rhythm is and how it can affect sleep

A circadian rhythm is a natural, internal process that regulates the sleep-wake cycle and repeats on each rotation of the Earth roughly every 24 hours.

ek = (m.v2) / 2

v - velocity of system after the collision

m = m1 + m2

ek = (m1 + m2) v2/2

ek = (200 + 250) 2,32/2 = 450*5,29/2 = 1190,25 j

by: nicholas dooley

see below  

explanation:

all of the above