A) 350 J
- The initial internal energy of the cup is
- The final internal energy of the cup is
According to the first law of thermodynamics:
where
Q is the heat absorbed by the system
W is the work done on the system
The work done on the system in this case is 0, so we can rewrite the equation as
And so we find the heat transferred
B) IN the cup
Explanation:
in this situation, we see that the internal energy of the cup increases. The internal energy of an object/substance is proportional to its temperature, so it is a measure of the average kinetic energy of the molecules of the object/substance. Therefore, in this case, the temperature (and the energy of the molecules of the substance) has increased: this means that heat has been transferred INTO the system from the environment (the heat came from the sun).
Conservation of energy explains that energy can only be transferred between different forms of energy
Answer:
One when it enters the glass slab from air and second time when it enters the air through glass slab. When light rays travelling through air enters glass slab, they get refracted and bend towards the normal. Now the direction of refracted ray changes again when it comes out of the glass slab into air.
In general,
Power = (energy moved) / (time to move the energy) .
If it's mechanical power, then
Power = (work done) / (time to do the work) .
If it's electrical power, then it can be any one of these:
Power = (volts) x (amperes)
Power = (volts)² / (resistance, ohms)
Power = (amperes)² x (resistance, ohms) .
Whatever kind of energy you're dealing with, power always
turns out to be
(amount of energy produced, used, or moved)
divided by
(time taken to produce, use, or move the energy) .
Answer:
B - Earth's path around the Sun
Explanation:
