Answer:
3.72 kJ
Explanation:
QH = 6.45 kJ
TH = 520 K
Tc = 300 K
Qc = ?
By use of Carnot's theorem
Qc / QH = Tc / TH
Qc / 6.45 = 300 / 520
Qc = 3.72 kJ
Answer:
Option A
The cost of keeping the semiconductor below the critical temperature is unreasonable
Explanation:
First of all, we need to understand what superconductors are. Superconductors are special materials that conduct electrical current with almost zero resistance. This means that there is little or no need for a voltage source to be connected to them. As a matter of fact, once a superconductor is connected to a power supply, one can remove the power supply and the current will still flow.
However, most superconducts can only conduct at very low temperatures up to -200 degrees Celcius. This is because, at that temperature, their atoms and molecules are relatively settled, hence they pose little or no resistance to the flow of current.
This as you can guess is extremely difficult to do, as you will need a lot of effort to cool it to that temperature and maintain it.
This makes option a the answer:
The cost of keeping the semiconductor below the critical temperature is unreasonable.
This instrument is called a spring scale.
Answer:
The reagents correspond to substances that react with others, generating a chemical reaction.
Explanation:
Example:
H2 + 02 -> H202
Hydrogen reacts with oxygen in a synthesis reaction, forming a new compound (hydrogen peroxide) called a product.
The period T of a pendulum is given by:
where L is the length of the pendulum while
is the gravitational acceleration.
In the pendulum of the problem, one complete vibration takes exactly 0.200 s, this means its period is
. Using this data, we can solve the previous formula to find L:
