The power expended doing 100 J of work in 50 s is 2 watts. This is calculated by dividing the work of 100 J by the time it took (50 s) to do that work. Since the unit for work is the joule (J) and the unit for time is the second (s), the resulting unit for power will be the watt (W).

Therefore, we can calculate the power as follows: Power = Work/ Time = 100 J / 50 s = 2 W.

## How many watts of power do you expend when you exert a force of 50 N that moves a crate 8 m in a time interval of 4 s?

The amount of power exerted when a force of 50N moves a crate 8m in a time interval of 4 s can be calculated using the formula for power (P) which is P = F x D/T, where F is the force in Newtons (N), D is the distance in metres (m) and T is the time period in seconds (s).

Using this formula, the total amount of power (in watts) exerted in the given situation would be:

P = 50 x 8 / 4 = 200 watts.

## What is the efficiency of a machine that puts out 100 W of power for every 1000 W put into it?

The efficiency of the machine is 10%. This is calculated by dividing the output power (100 W) by the input power (1000 W) and multiplying the result by 100. Therefore, the machine has an efficiency of 10%, meaning it outputs 10 W of power for every 100 W put into it.

## What is J in potential energy?

J, or joule, is a unit used to measure potential energy. Potential energy is the stored energy of an object that is ready to be used in the event of an action taking place. The amount of potential energy an object has depends on its mass, distance from the Earth’s center, and gravity.

The higher the mass, the farther away from the center, and the greater the gravitational force, the more potential energy the object has. J is a measure of the amount of energy stored in the object that can be converted to other forms of energy, such as kinetic energy, when needed.

It is also the standard unit of energy used in the International System of Units (SI).

## How do you calculate potential energy at work?

Potential energy at work is typically calculated using the equation PE = mgh, where m is the mass of the object, g is the acceleration due to gravity, and h is the height of the object. To calculate potential energy, you can determine the mass, the acceleration due to gravity, and the height of the object, then use the equation.

For example, if an object is 8kg and located 3m above the ground, the potential energy can be calculated using: PE = 8kg * 9. 8m/s² * 3m = 235. 2J. This is the potential energy of the object at the given location.

## How do you calculate power efficiency?

Power efficiency can be calculated by dividing the amount of power output (measured in watts) by the amount of power input (again measured in watts). This ratio is then multiplied by 100 to express it in terms of a percentage.

For example, if 100 watts of power is put into a motor, and it produces 75 watts of power, then the power efficiency would be calculated as follows:

75 watts / 100 watts = 0.75

0.75 x 100 = 75% power efficiency.

It is important to note that this calculation must take into account any power losses that resulted from heat, friction or other environmental factors. For example, if the 100 watts of power input results in only 72 watts of power output, then the power efficiency would need to be adjusted accordingly.

This can be done by subtracting the losses from the power output, and then dividing this number by the power input. For example:

72 watts – 8 watts = 64 watts

64 watts / 100 watts = 0.64

0.64 x 100 = 64% power efficiency.

In other words, power efficiency represents the amount of power that is being effectively used as opposed to lost. Knowing the power efficiency of your electrical, mechanical or other system can help you identify areas of energy loss, and hopefully make adjustments to reduce the losses and increase the efficiency.

## How much work can a 22 kW car engine do in 60s if it is 100% efficient?

At 100% efficiency, a 22 kW car engine can do 13,320 Joules of work in 60s. In terms of power, this is equivalent to 2,200 watts. This is the maximum amount of work the engine can do in 60s if it is 100% efficient.

In real-world conditions, however, car engines typically operate far below 100% efficiency and therefore will not be able to do as much work in the same amount of time.

## What amount of work is done when a force of 50 N?

The amount of work done when a force of 50N is applied depends on how far the force is applied. Work is defined as the force multiplied by the distance it is applied, meaning the equation for work done is W=F*d.

If the force of 50N is applied over a distance of 1 meter, the amount of work done is 50 Joules. If the same force of 50N is applied over a distance of 2 meters, then the total work done would be 100 Joules, and so on.

Therefore the amount of work done by a force of 50N depends on how far the force is applied.

## What will be the kinetic energy of an arrow having a potential energy of 50 J after it is shot from a bow?

Once the arrow is shot from the bow, its potential energy will transform into kinetic energy. Its kinetic energy will depend on the speed at which it is released and the mass of the arrow. To calculate its kinetic energy, we can use the equation KE = 1/2 × m × (v^2) where m is the mass of the arrow and v is the arrow’s velocity.

Assuming the arrow is fired with an initial velocity of 25 meters per second, its kinetic energy will be 625 joules (50J + 1/2 × 0. 05 kg × (25 m/s)^2 ).

## When the work done is 100%?

The work is 100% done when the project meets or exceeds the criteria that was set when the work began. This typically occurs when all of the tasks assigned have been completed, a final review of the work has been conducted to identify any potential problems and all feedback has been incorporated.

Additionally, everyone involved with the project agrees that the results meet the requirements that they were asked to achieve. At this point, the project can be considered 100% complete.

## What is the work done formula?

The work done formula is the mathematical expression used to calculate the amount of work that is done by a force in a particular direction. It is expressed as the product of the force (F), the distance (d) that the force is applied, and the cosine of the angle between the force and the displacement (θ).

Mathematically, it is expressed as W = F∙ d∙ Cosθ, where W is the work done.

Work done can also be calculated as the change in energy (ΔE) over the change in time (Δt). This equation is expressed as W = ΔE/Δt.

The work done formula is used to calculate the energy and power input and output in physical systems. It is one of the four fundamental equations of mechanics and forms the basis for many of the concepts used in physics and engineering.

## What is the formula of energy?

The formula for energy is one of the most fundamental equations in physics, known as the Law of Conservation of Energy. It states that energy can neither be created nor destroyed, but can only be transferred from one form to another.

The formula is represented as: E=mc², where E is energy, m is mass, and c² is the speed of light squared. This equation indicates that energy is created when matter is accelerated to the speed of light, and therefore, the faster an object is moving, the more energy it contains.

This explains why, for example, an object with a higher velocity has more energy than an object with a lower velocity. The Law of Conservation of Energy applies to all forms of energy, including mechanical, electrical, chemical, thermal, and even gravitational energy.

## What is a 100% efficient machine called?

A 100% efficient machine is a theoretical machine that converts all input energy into an equivalent amount of output energy without any loss of energy in the process. This machine would not require any kind of external energy source, as it would be able to convert all input energy into output energy regardless of the form of the input.

This would not necessarily mean that all of the input energy could be used for any given purpose, but that all of the energy would be made available for use in some form. Examples of 100% efficient machines include the idea of a Carnot cycle engine, the Stirling engine, or a heat engine operating at the ambient temperature.

Such a machine would be able to convert heat energy from a warm external source into useful work. Unfortunately, a 100% efficient machine is impossible in reality, with the most thermally efficient machines reaching efficiencies of up to around 62-63%.

## What machine is 100 percent efficient?

All machines have some losses due to things like friction, energy conversion, and other factors that prevent them from reaching 100 percent efficiency. Factors like the quality of the parts used in the machine, the environment they are operated in, and the maintenance of the machine can all affect the overall efficiency, but no machine is capable of reaching perfect efficiency.

## Which has greater kinetic energy?

The answer as to which has greater kinetic energy depends on the object or objects in question. Kinetic energy is the energy a body possesses due to its motion, and is defined as the energy which an object has because of its motion.

Kinetic energy is calculated by multiplying the mass of the object by the velocity squared and then dividing by two. Therefore, when comparing two objects in terms of kinetic energy, the object with the greater mass and/or velocity generally has the greater kinetic energy.

For example, a large freight train moving at 20 km/h has more kinetic energy than a smaller car moving at 10 km/h since the freight train is much larger and moving faster. Similarly, two cars moving at the same speed, but a large car having greater mass than a smaller car, will also have greater kinetic energy.