Why Is Average Thermal Power Not Negative in This Friction Scenario?

In summary, the concept of average thermal power in a friction scenario remains non-negative due to the principles of thermodynamics and energy conservation. Even though friction generates heat, which could suggest energy loss, the system’s average thermal power reflects the balance between input energy and energy dissipated. The heat produced by friction is a manifestation of energy transformation rather than a deficit, ensuring that average thermal power does not fall below zero.
  • #1
yashboi123
17
0
Homework Statement
A 20.0 kg rock is sliding on a rough, horizontal surface at 8.00 m/s and eventually stops due to friction. The coefficient of kinetic friction between the rock and the surface is 0.200.
Relevant Equations
P = F . v
P = Fvcos(x)
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I'm curious as to why the average power is not negative in this scenario, since I thought the friction force is in the opposite direction of velocity. As far as I see friction force is the only acting force in the problem, but I may be wrong. I solved this by simply doing (Friction Force * (v/2)), the average velocity.
 
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  • #2
yashboi123 said:
I'm curious as to why the average power is not negative in this scenario
Because it asks for the thermal power produced, not the work per unit time done on the rock. The friction force the rock exerts on the surface is in the same direction as its velocity.
 

FAQ: Why Is Average Thermal Power Not Negative in This Friction Scenario?

What is average thermal power produced?

Average thermal power produced refers to the mean amount of heat energy generated by a power plant or system over a specified period. It is typically measured in units like megawatts (MW) or gigawatts (GW).

How is average thermal power produced calculated?

Average thermal power is calculated by summing the total thermal energy produced over a given time period and then dividing by the duration of that period. The formula is: Average Thermal Power = Total Thermal Energy / Time Period.

What factors influence the average thermal power produced?

Several factors can influence average thermal power, including the efficiency of the power plant, the type of fuel used, the operational hours, maintenance schedules, and environmental conditions such as temperature and humidity.

Why is it important to monitor the average thermal power produced?

Monitoring the average thermal power produced is crucial for optimizing the efficiency and performance of power plants, ensuring reliable energy supply, managing fuel consumption, and reducing environmental impact by monitoring emissions.

How does average thermal power produced differ from peak power output?

Average thermal power produced represents the mean power output over a period, while peak power output refers to the maximum power generated at any single point in time. Peak power is usually higher and can indicate the plant's capacity to handle demand surges.

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