The efficiency of a heat engine is given by the expression 
The efficiency of a heat engine is the ratio of the work done by the engine to the heat given as the input to the engine.

The heat engine absorbs Q h from the hot reservoir , performs a work <em>W</em> on the absorbed heat and rejects Qc to the cold reservoir.
Therefore, the work done is given by,

Thus the efficiency is given by, 
Answer:
The answer to your question is : 521.8 m
Explanation:
Data:
Different heights
Time first object (tfo) = 10.7 s
Time second object (tso)= 14.8 s
Initial speed of both objects(vo) = 0 m/s
a = 9.81 m/s²
Formula:
h = vot + 1/2 (a)(t)² but vo = 0 so, h = 1/2 (a)(t)²
Then, height fo h = 1/2 (9.81)(10.7)² = 561.6 m
height so h = 1/2(9,81)(14.8)² = 1074.4 m
Difference in their heights = 1074.4 m - 561.6 m = 521.8 m
Answer: Car brakes produces more energy then the bicycle because the cars wheels produces a much bigger force that makes the car go and to stop that force the car uses greater amount of energy that transfers to heat but in a bicycle the wheels do not turn that fast so when you press the break there is less energy that transfer to heat.
Explanation:
The correct answer is:
<span>Point charges must be in a vacuum.
In fact, the usual form for of the Coulomb's law is:
</span>

<span>where
</span>

is the permittivity of free space
<span>q1 and q2 are the two charges
q is the separation between the two charges
However, this formula is valid only if the charges are in vacuum. If they are in a material medium, the law is modified as follows:
</span>

where

is the relative permittivity, which takes into account the dielectric effects of the material.
Answer:
D
Explanation:
induction is the transfer of charge without contact between materials