In the blank should go of friction.
Answer:
10500 J/kg/*C
Explanation:
Quantity of heat required=mass of substance x specific heat capacity x change in temperature
Quantity of heat required=0.25 x 4200 x [30-20]
Quantity of heat required=0.25 x 4200 x 10
Quantity of heat required=10500 J/kg/*C
In order to accelerate the dragster at a speed

, its engine must do a work equal to the increase in kinetic energy of the dragster. Since it starts from rest, the initial kinetic energy is zero, so the work done by the engine to accelerate the dragster to 100 m/s is

however, we must take into account also the fact that there is a frictional force doing work against the dragster, and the work done by the frictional force is:

and the sign is negative because the frictional force acts against the direction of motion of the dragster.
This means that the total work done by the dragster engine is equal to the work done to accelerate the dragster plus the energy lost because of the frictional force, which is

:

So, the power delivered by the engine is the total work divided by the time, t=7.30 s:

And since 1 horsepower is equal to 746 W, we can rewrite the power as
The work needed if a force of 3N is used to move a table 25 metres is 75Nm (joules).
<h3>How to calculate work done?</h3>
Work is a measure of energy expended in moving an object. This means that no work is done if the object does not move.
Force is a physical quantity that denotes the ability to push, pull, twist or accelerate a body and which has a direction and is measured in Newtons.
Work done on an object can be calculated by multiplying the force applied to move the object by the distance the object moves as follows:
Work done = Force (N) × distance (m)
According to this question, a force of 3 Newtons is used to move a table over a distance of 25 meters. The work done on the table can be calculated as follows;
W = 3N × 25metres
W = 75Nm
Therefore, 75Nm is the work done on the table.
Learn more about work done at: brainly.com/question/2117638
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To solve this we can use one of the main four kinematic equations, preferably we want something that we can use directly without solving for other values.
So in this problem we know that:
Inital velocity or Vi = 0 (started from rest)
The acceleration of the object = 7.5
The distance the object travels Δx = 87m
So, our best equation here with what we have would be:
Vf² = Vi² + 2aΔx
Now we now that Vi is 0 so:
Vf² = 2aΔx
We need final velocity so lets take the square root of Vf to isolate it:
Vf = √2aΔx
Now we plug in
Vf = √2(7.5)(87)
Vf = 36.124 m/s or 36.1 m/s