Answer:
The error he made was that he didn't convert the unit of temperature to Kelvin.
The correct efficiency is 24%
Explanation:
Parameters given:
Temperature of hot reservoir = 100°C = 373 K
Temperature of cold reservoir = 10°C = 273 K
The efficiency of a heat engine is given as:
E = 1 - (Qc/Qh) = 1 - (Tc/Th)
Where
Qc = Output heat;
Qh = Input heat;
Tc = Temperature of the cold reservoir;
Th = Temperature of the hot reservoir.
=> E = 1 - (283/373)
E = 1 - 0.76
E = 0.24
In percentage,
E = 0.24 * 100 = 24%
Hence, the efficiency of the engine is actually 24%.
The error he made was that he didn't convert the temperature to Kelvin. If we leave the temperatures in °C, we have that:
E = 1 - (10/100)
E = 1 - 0.1 = 0.9
In percentage,
E = 0.9 * 100 = 90%
The answer to the question is A
When an object moves its length contracts in the direction of motion. The faster it moves the shorter it gets in the direction of motion.
The object in this question moves and then stops moving. So it's length first contracts and then expands to its original length when the motion stops.
The speed doesn't have to be anywhere near the speed of light. When the object moves its length contracts no matter how fast or slow it's moving.
Answer:
The formula of energy is m
. So, energy is M
. Since velocity = displacement/time.
Explanation:
If you have any questions feel free to ask in the comments - Mark
Answer:
Magnetic field will be ZERO at the given position
Explanation:
As we know that the magnetic field due to moving charge is given as
so here we know that for the direction of magnetic field we will use
so we have
so magnetic field must be ZERO
So whenever charge is moving along the same direction where the position vector is given then magnetic field will be zero
