a = ( v(2) - v(1) ) ÷ ( t(2) - t(1) )
2 = ( v(2) - 10 ) ÷ ( 6 - 0 )
2 × 6 = v(2) - 10
v(2) = 12 + 10
v(2) = 22 m/s
It's not so much a "contradiction" as an approximation. Newton's law of gravitation is an inverse square law whose range is large. It keeps people on the ground, and it keeps satellites in orbit and that's some thousands of km. The force on someone on the ground - their weight - is probably a lot larger than the centripetal force keeping a satellite in orbit (though I've not actually done a calculation to totally verify this). The distance a falling body - a coin, say - travels is very small, and over such a small distance gravity is assumed/approximated to be constant.
Melatonin is a hormone being produced by small gland in the brain called pineal
gland that helps control sleep and wake cycles. It is also called the sleep
hormone because it gives signal that it’s time to sleep. People
also used this hormone to adjust the body’s internal clock. It is the hormone
that released in response to exposure to sunlight. When the sun sets and night
falls, the pineal is activated and begins to vigorously produce melatonin. The
amount of melatonin tends to rise as night falls, peaks at midnight, and falls
again as the sun rises. It means that it produced more when darker and when the
lighter it is; the less melatonin is produced.
Answer:
Viscosity is a measure of how much a liquid resists flowing freely.