Answer:
v = 26.7 mph
Explanation:
During the first 5 hours, at a constant speed of 20 mph, we find the total displacement to be as follows:
Δx₁ = v₁*t₁ = 20 mph*5 h = 100 mi
Assuming we can neglect the displacement during the speeding up from 20 to 60 mph, we can find the the total displacement at 60 mph as follows:
Δx₂ = v₂*t₂ = 60 mph*1 h = 60 mi
So, the total displacement during all the trip wil be:
Δx = Δx₁ + Δx₂ = 100 mi + 60 mi = 160 mi
So we can find the the average velocity during the 6-hour period, applying the definition of average velocity, as follows:
v = Δx / Δt = 160 mi / 6 h = 26.7 mph
The law of conservation of energy is:
-- Energy can't be created or destroyed.
-- Energy can't just appear out of nowhere. If you suddenly have
more energy, then the 'extra' energy had to come from somewhere.
-- Energy can't just disappear. If you suddenly have less energy,
then the 'missing' energy had to go somewhere.
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There are also conservation laws for mass and electric charge.
They say exactly the same thing. Just write 'mass' or 'charge'
in the sentences up above, in place of the word 'energy'.
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And now I can tell you that the conservation laws for energy and mass
are actually one single law ... the conservation of mass/energy. That's
because we discovered about 100 years ago that mass can convert
into energy, and energy can convert into mass, and it's the total of BOTH
of them that gets conserved (can't be created or destroyed).
How much mass makes how much energy ?
The answer is E = m c² .
Answer: The plasma membrane is called a selectively permeable membrane as it permits the movement of only certain molecules in and out of the cells. Not all molecules are free to diffuse. If plasma membrane ruptures or breaks down then molecules of some substances will freely move in and out of the cells.
Answer:
The rate at which velocity changes with respect to a change in time is called. acceleration.
Explanation:
