Answer: B
Explanation:
A machine multiplies the work output of a something by some amount. In this question, the ax is the machine. Thus, the ax is multiplying the work outputted by the lumberjack, so the answer is B. The reason it is not C is because there could be other forces interacting on the wood which the ax can affect.
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%
To solve this problem it is necessary to apply the concepts given by Malus regarding the Intensity of light.
From the law of Malus intensity can be defined as
Where
Angle From vertical of the axis of the polarizing filter
Intensity of the unpolarized light
The expression for the intensity of the light after passing through the first filter is given by
Replacing we have that
Re-arrange the equation,
Re-arrange to find \theta
The value of the angle from vertical of the axis of the second polarizing filter is equal to 30.2°
The answer to your question is,
4 kilometers north
-Mabel <3
