Basic Energy Problem (Concept)

In summary: Since the particle is not allowed to move in this direction, the work done by this normal force is zero, and the total work done by all forces acting on the particle is also zero, according to the work-energy theorem.In summary, the total work done on a particle on a frictionless surface is zero because the normal force acting perpendicular to the surface does not do any work. This is due to the fact that the surface constrains the motion of the particle.
  • #1
xtrubambinoxpr
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0

Homework Statement



See the picture attached please. I need help understanding the concept of why work is = 0. I don't understand it's explanation. Please bare with me for the silly questions.


Homework Equations



W=Kf-Ki

W=Fdcosθ

The Attempt at a Solution



I can't understand why It mentions the normal force acting perpendicular if its being pushed to the left not up.
 

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  • #2
xtrubambinoxpr said:
See the picture attached please. I need help understanding the concept of why work is = 0.
The total work is zero, since the kinetic energy doesn't change. Look up the work-energy theorem.

I can't understand why It mentions the normal force acting perpendicular if its being pushed to the left not up.
The object is moving parallel to the the ramp, but the normal force acts perpendicular to it. So does the normal force do any work in this case?
 
  • #3
Doc Al said:
The total work is zero, since the kinetic energy doesn't change. Look up the work-energy theorem.


The object is moving parallel to the the ramp, but the normal force acts perpendicular to it. So does the normal force do any work in this case?


You will have to dumb it down a good amount for me =/
 
  • #4
xtrubambinoxpr said:
I can't understand why It mentions the normal force acting perpendicular if its being pushed to the left not up.

If a particle moves on a frictionless rigid surface, due to the fact that this surface constrains the motion of the particle, we have an additional force acting (locally) perpendicularly to the surface.
 
  • #5


First of all, there are no silly questions when it comes to learning and understanding new concepts. It is important to ask questions in order to fully grasp a concept. So, do not worry about that.

Now, let's look at the basic energy problem. The concept of work is defined as the transfer of energy from one object to another by the application of a force. In this problem, we have an object being pushed to the left with a certain amount of force. However, the object does not move because there is an equal and opposite force acting on it, known as the normal force.

In this case, the normal force is acting perpendicular to the direction of the force pushing the object. This means that the work done by the normal force is zero, since the force and displacement are perpendicular to each other (cosθ=0). Therefore, the net work done on the object is also zero, as the work done by the force pushing the object is equal and opposite to the work done by the normal force.

To understand this concept better, you can think of it in terms of energy. The object has a certain amount of kinetic energy (Kf) before it is pushed. When the force is applied, it does not move, so its kinetic energy remains the same. This means that the work done by the force must be equal to the work done by the normal force, in order for the object's kinetic energy to remain constant.

I hope this helps to clarify the concept for you. If you still have any questions, please do not hesitate to ask.
 

1. What is the basic energy problem concept?

The basic energy problem concept refers to the challenge of meeting the energy demands of society while minimizing negative impacts on the environment and economy. It involves understanding and managing the production, distribution, and consumption of energy resources.

2. What are the main sources of energy?

The main sources of energy include fossil fuels (such as coal, oil, and natural gas), renewable resources (such as solar, wind, and hydropower), and nuclear energy. Each source has its own advantages and disadvantages, and a combination of these sources is often used to meet energy demands.

3. How does energy consumption affect the environment?

Energy consumption has a significant impact on the environment. The burning of fossil fuels releases greenhouse gases, contributing to climate change. Extracting and using these fuels also leads to air and water pollution. Renewable energy sources have a smaller environmental footprint, but can still have impacts on ecosystems and habitats.

4. What are some solutions to the basic energy problem?

There are several solutions to the basic energy problem, including improving energy efficiency, investing in renewable energy sources, and implementing sustainable energy policies. Other solutions include promoting energy conservation, developing new technologies for clean energy production, and encouraging global cooperation in addressing energy issues.

5. How can individuals contribute to solving the basic energy problem?

Individuals can contribute to solving the basic energy problem by making small changes in their daily lives, such as using energy-efficient appliances and vehicles, reducing energy consumption, and supporting renewable energy initiatives. Educating oneself and others about energy issues and advocating for sustainable energy policies can also make a positive impact.

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