Is Holding a Weight at Arm's Length Considered Work?

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In summary, the boy holding a 40N weight at arm's length for 10s, with his arm 1.5m above the ground, would not be doing any work as there is no displacement of the object. This means that the work done by the force of the boy on the weight he is holding is zero.
  • #1
blackout85
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A boy holds a 40N weight at arm's length for 10s. His arm is 1.5m above the ground. The work done by the force of the boy on the weight he is holding. He would not be doing any work, because their is no motion and he is lifting it up.

Thank you
 
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  • #2
blackout85 said:
He would not be doing any work, because their is no motion and he is lifting it up.

A better way to state the answer would be to say that the displacement of the object is zero. For if he had taken the object along some crazy path and brought it back to where he started, the work done would still be zero, even though the object had moved.
 
  • #3
for your question. I would like to clarify some concepts related to work and provide a response to your content. Firstly, work is defined as the product of force and displacement in the direction of the force. In simpler terms, work is done when a force causes a displacement. In this scenario, the boy is indeed exerting a force of 40N on the weight he is holding and there is a displacement of 1.5m in the upward direction. Therefore, work is being done.

However, it is important to note that the work done by the boy on the weight is equal to the work done by the weight on the boy's arm, as per Newton's Third Law of Motion. This means that while the boy is exerting a force to lift the weight, the weight is also exerting an equal and opposite force on the boy's arm. This results in no net work being done on the system of the boy and the weight.

In this case, the boy's arm is not moving and there is no change in the position of the weight. This means that there is no change in the potential energy of the system and hence, no work is being done. However, the boy is still exerting a force and using energy to hold the weight at arm's length. This can be considered as isometric or static work, where there is no movement but energy is still being expended.

In conclusion, the boy is indeed doing work by exerting a force on the weight, but there is no net work being done on the system as there is no change in the potential energy. I hope this clarifies any confusion and helps to better understand the concept of work. Thank you.
 

Related to Is Holding a Weight at Arm's Length Considered Work?

What is the definition of "work" in science?

In science, work is defined as the transfer of energy from one system to another. It is typically measured in joules (J) and is calculated by multiplying the force applied to an object by the distance it moves in the direction of the force.

How is work related to other scientific concepts, such as power and energy?

Work, power, and energy are all related concepts in science. Work is the transfer of energy, while power is the rate at which work is done. Energy is the ability to do work, and it can come in various forms such as kinetic, potential, thermal, and chemical energy.

What are some examples of work in everyday life?

Some examples of work in everyday life include pushing a shopping cart, lifting a book, and climbing stairs. In each of these cases, a force is applied to an object, causing it to move a certain distance.

What are the different types of work in physics?

In physics, there are two main types of work: positive work and negative work. Positive work occurs when a force is applied in the same direction as the displacement of an object, while negative work occurs when the force is applied in the opposite direction of the displacement.

How is work calculated and measured in science?

Work is calculated by multiplying the force applied to an object by the distance it moves in the direction of the force. It is typically measured in joules (J), but other units such as calories and foot-pounds can also be used.

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