so first your going to use v=Δd/Δt given you the answer 80 i think that's right
A. To find work we need to know F and S; to find power we need to know F and V
I racked my brain for almost 10 minutes, until suddenly,
it hit me !
You're breathing one right now ! So am I .
Air is a mixture of a lot of elements.
Nitrogen, Oxygen, and Argon account for 99.964 percent.
The other 0.036 percent is mainly Neon, Helium, Krypton,
and Hydrogen ... more elements.
Then there are Carbon Dioxide and water vapor.
Yes, those are compounds. But together, they add up
to very little of the air we breathe, and if both of them
suddenly disappeared, we would hardly notice it.
The answer is C. Convection.
Radiation is the transfer of energy through electromagnetic waves. Conduction, on the other hand, is energy transfer through solid material. Condensation occurs when warm gas makes contact with a cold surface or environment, which causes a change in state from gas to liquid. These definitions rule out choices A, B, and D.
Convection is movement of particles in fluid or gas. As liquid/gas heats up, it becomes less dense and rises, moving away from the heat source. When it rises, it eventually cools down and sinks again. It is warmed up again and the cycle continues. This is why there is a circular motion when convection occurs.
Answer:
(a) 
(b) 
Explanation:
The average power is defined as the amount of work done during a time interval:
According to work-energy theorem, the work done is equal to the change in kinetic energy. So, we have:
Recall that the weight is given by:
The car accelerates uniformly from rest (
). Replacing (3) in (2), we have:
(a) Finally, we replace this in (1):
(b)
