A) 350 J
- The initial internal energy of the cup is
- The final internal energy of the cup is
According to the first law of thermodynamics:
where
Q is the heat absorbed by the system
W is the work done on the system
The work done on the system in this case is 0, so we can rewrite the equation as
And so we find the heat transferred
B) IN the cup
Explanation:
in this situation, we see that the internal energy of the cup increases. The internal energy of an object/substance is proportional to its temperature, so it is a measure of the average kinetic energy of the molecules of the object/substance. Therefore, in this case, the temperature (and the energy of the molecules of the substance) has increased: this means that heat has been transferred INTO the system from the environment (the heat came from the sun).
Hydraulic jacks, automobile brakes and even the lift generated on airplane wings can be explained using Pascal's principle. Pascal's principle is based on the idea that fluids at rest are incompressible, allowing very large forces to be transmitted with the application of a smaller force.
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Answer:</h3>
4 m/s²
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Explanation:</h3>
From the question, we are given;
- Mass of the ball is 2.0 kg
- Acceleration of the ball is 4.2 m/s²
With the above information, we can calculate the force applied to the ball.
- From the second newton's law of motion, F = ma
- Therefore;
Net force, F = 2.0 kg × 4.2 m/s²
= 8.4 N
- We are required to determine the acceleration when the same force is applied to a steel ball with a mass of 2.1 kg.
Mass = 2.1 kg
Force = 8.4 N
But;
Force = mass × acceleration
Acceleration = Force ÷ Mass
= 8.4 N ÷ 2.1 kg
= 4 m/s²
Thus, the acceleration will be 4 m/s²
A roller coaster is stopped on a track. When the engineer presses a launch button on the coaster, the coaster moves forward. Explain this change in terms of balanced and unbalanced forces.