Calculating Wasted Energy: The Efficiency of Force Applied at an Angle

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In summary: He mentions that if we measure the force applied to a blocked object and then measure the outcome of that force, we can deduce the amount of energy wasted. He also brings up the concept of efficiency and how it relates to the amount of energy burned or used. In summary, Chet explains that when pulling an object at a 45° angle, the work done is still the same as if pulling it along the track. However, the force needed to push the object up the incline is less, resulting in a lower amount of energy wasted.
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bobie
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Edit: Suppose you are pulling a weight along a track at an angle (in the picture 45°).
horse pulling a cart on a track

If the object is dislocated by a distance D let's assume that the work done/energy tranmitted to the object is $E_{45}$ = K J. If you had pulled along the track, would the distance covered by the object be $D_0$ = K/cos45° and $E_0$ = K/cos45 = 1.41 * K? if this is correct, can we conclude that the energy wasted/ calories burned doing no mechanical work is 41 %?.

(If this is not correct, how can we calculate the energy wasted when we apply a force at an angle greater than 0°?)

I know that no mechanical work in excess is done, that is because of the peculiarity of the definition of work. I tried to dodge this ostacle speaking of *calories burned*: I thought we can desume that by reverse engineering.

The logic is this: we have instruments (I am referring to instruments, so we avoid inefficiency of human muscles) to produce and measure force. If we measure the force something exerts on a blocked object, then remove the block and measure the oucome of that force, can't we deduce that the same force has been applied before and the **same amount of energy/calories has been wasted?**
If this logic is valid, the same logic has been applied to the horse.

A biologist can tell us the percentage of calories burned in excess of the effective force applied/ transmitted, the inefficiency of the human machine is around 80%: you burn 4 - 5 times more energy than you put to avail. Efficiency may vary from 18% to 26%. In the case above energy actually burned would be 41*4.5 = ca. 185%
 
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Weight is proportional to mass, which doesn't directly determines the force you are pushing object with. The fact that you pushed object weighing 100N (cc 11kg) for 1 meter doesn't mean that work done is 100 j.
 
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I assume the track is an incline, and it rises vertically a distance of 1 meter, so that the distance you push the weight up the incline is 1.41 meters. But the force you need to exert to push the weight up the incline is only 70.7 N. So the work is still 100 joules.

Chet
 

1. What is wasted energy?

Wasted energy refers to the energy that is lost or dissipated during a process or action. In the context of calculating the efficiency of force applied at an angle, it refers to the energy that is not used to perform the desired task or movement, but instead is lost in the form of heat, sound, or other forms of energy.

2. How is wasted energy calculated?

Wasted energy can be calculated by subtracting the useful energy output from the total energy input. In the context of calculating the efficiency of force applied at an angle, it involves determining the component of force that is parallel to the direction of motion and comparing it to the total force applied.

3. What factors affect the efficiency of force applied at an angle?

The efficiency of force applied at an angle is affected by several factors, including the angle of application, the magnitude of force, and any external factors such as friction or air resistance. Additionally, the type of surface and the materials involved can also impact the efficiency of force applied at an angle.

4. How is the efficiency of force applied at an angle expressed?

The efficiency of force applied at an angle is typically expressed as a percentage. It is calculated by dividing the useful energy output by the total energy input and multiplying by 100. The resulting percentage represents the proportion of energy that is effectively used to perform the desired task or movement.

5. What are some real-life applications of calculating wasted energy?

Calculating wasted energy can have practical applications in various fields, such as engineering, physics, and sports. For example, engineers can use this concept to improve the design and efficiency of machines and structures. In sports, athletes can use this knowledge to optimize their movements and improve their performance. Additionally, understanding wasted energy can also help in making more sustainable and energy-efficient choices in daily life.

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