<span>In a
real machine, the work output is always less than the work input is true. The answer
is letter A. it follows the law of entropy where no energy can be converted completely
into work. Under this law, Carnot’s theorem states that Carnot’s engine can
perform 100% of work. However, no such engine has ever succeeded the conversion
of work into 100%. The greatest efficiency so far is at 80%. Because there will always be factors that
could affect the conversion of work. </span>
Is proportional to the CHANGE.
hope this helps
Answer:
v = 98.75 km/h
Explanation:
Given,
The distance driver travels towards the east, d₁ = 135 km
The time period of the travel, t₁ = 1.5 h
The halting time, tₓ = 46 minutes
The distance driver travels towards the east, d₂ = 215 km
The time period of the travel, t₁ = 2 h
The average speed of the vehicle before stopping
v₁ = d₁/t₁
= 135/1.5
= 90 km/h
The average speed of vehicle after stopping
v₂ = d₂/t₂
= 215/2
= 107.5 km/h
The total average velocity of the driver
v = (v₁ +v₂) /2
= (90 + 107.5)/2
= 98.75 km/h
Hence, the average velocity of the driver, v = 98.75 km/h
We make use of the equation: v^2=v0^2+2a Δd. We substitute v^2 equals to zero since the final state is halting the truck. Hence we get the equation -<span>v0^2/2a = Δd. F = m a from the second law of motion. Rearranging, a = F/m
</span>F = μ Fn where the force to stop the truck is the force perpendicular or normal force multiplied by the static coefficient of friction. We substitute, -v0^2/2<span>μ Fn/m</span> = Δd. This is equal to
