The thermal efficiency of an engine is

where
W is the work done by the engine
Q is the heat absorbed by the engine to do the work
In this problem, the work done by the engine is W=200 J, while the heat exhausted is Q=600 J, so the efficiency of the machine is
Acceleration is any change in speed or direction of motion.
The dimension of speed is [length/time],
so a change is [length/time²].
Popular units include [meter/second²] and [feet/second²] .
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Direction almost always boils down to an angle, (which technically
has no dimensions), so a change in direction is [angle/time] .
Popular units include [radian/second] and [degree/second] .
In order to find the our own velocity with respect to land,we need to apply the theory of relative velocity.
Now consider the velocity of the ship traveling towards the north with respect to land as A.Consider our own velocity headed northwards as B.
The relative velocity is the velocity that the body A would appear to an observer on the body B and vice versa.
In this case the relative velocity would be arrived by summing up our velocity with the velocity of the ship as the object (I) is travelling in the ship.
Relative velocity = Velocity of Body A+ Velocity of Body B.
Velocity of the ship traveling towards the north with respect to land(A)= 13.0m/s. (Given)
Our own velocity headed northwards(B)= 2.8 m/s.
Relative velocity = Velocity of Body A+ Velocity of Body B.
Relative velocity= 13.0 + 2.8 = 15.8m/s.
Thus our own velocity with respect to the land is 15.8 m/s.
Explanation:
"The burning of fossil fuels , oil and natural and power from nuclear power provide about 87% of the energy used in the world.
Coal, natural gas, petroleum and nuclear power are the major energy providers to the whole world. Till date we are heavily depend on them. They provide for about 87% of the total energy used in the world.
The question "<span>In a redox reaction the substance that accepts electrons is said to be?" is a bit vague. By definition, a "redox" or "reduction" reaction is one where classified by a gain of electrons. On the other hand, if it is a loss of electrons, then it is an oxidation reaction.</span>