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When isolating two or more wires the installer can rely on what electrical component?

Any reference to isolating electrical components, an insulator is the first choice.


What are DC motors?

A DC motor is any of a class of electrical machines that converts direct current electrical power into mechanical power. The most common types rely on the forces produced by magnetic fields. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic, to periodically change the direction of current flow in part of the motor. Most types produce rotary motion; a linear motor directly produces force and motion in a straight line.


What are the advantages of having all power stations connected to the National Grid?

More power on peak times If one goes down, they can rely on the other power stations


Costs of electric floor heating?

One type of heating for the floors that is a bit less expensive is the geothermal heating. These pumps rely on water pipes that are layed in the subfloor and when water moves through them the heat (or cold for that matter) radiates to the tiles above and generates heat or cooling.


Why is using a variable resistor in parallel with a motor not the best way of controlling its speed?

By connecting a resistor in parallel to an electric motor to control its speed is bad practice. One would then be using the internal resistance of your source to reduce the voltage that drive the motor. In some cases it is not only insufficient but also dangerous because you might short circuit or overload your source. In very low power applications with small motors, having a series resistor will work just fine (resistor in line with the motor) With higher power AC circuits a choking coil may be used. Then you rely on the inductance of the coil to increase impedance without converting all the unused energy into heat. The problem with resistors are that if your motor need to run on 6V in order to draw 1 ampere to produce 6 watt power and you obtained that by using a 12V supply with a resistor in series. Then the supply will deliver 12V x 1A = 12W and the motor will use 6V x 1A = 6W, what happens to the other 6W? it is dissipated by the resistor, the resistor will convert that unused energy into heat. This method is not very energy efficient and can become difficult to keep the resistor cool. Ideally when larger motors are used. The use of PWM (Pulse Width Modulation) becomes essential. PWM allow you to switch the motor on and off at high frequency. When the power is on and no resistance is in series. Then all energy goes to the motor to be effectively used resulting in high efficiency. Then, when the supply is in off state, then no power is consumed at all. This will also result in very low energy loss. Thus, regardless whether the power is on or off there is always very little energy wasted. If 12W is delivered when the supply is on and 0W is delivered when it is off. Should the pulse be on 50% of the time and off for the other 50% of the time. We will call it a 50% duty cycle (d.c.). The average power delivered will be 6W since it only deliver 12W half of the time. But since the 12W and 0W periods are both low energy loss states due to low resistance. The average 6W will also be delivered at high efficiency and almost no extra energy will be wasted on heat. It makes sense, when you want to reduce the speed of a 100kW motor. Then using a resistor with a 50 000 W rating, baring in mind that 50 000W may be dissipated as heat. Then the "cooling towers" required to keep the resistor cool will be a bit absurd. Paying for an extra 50 000 W, what is not used will not do your business any good either.

Related Questions

Does light bulb converts kinetic energy into electrical energy?

No, a light bulb does not convert kinetic energy into electrical energy. Light bulbs rely on electrical energy to produce light. The kinetic energy of moving objects is not directly converted into electrical energy to power the light bulb.


What is a non thermal energy?

Non-thermal energy refers to energy that is not related to heat or temperature, such as electrical energy, light energy, and kinetic energy. It does not rely on changes in temperature to be generated or consumed.


How does energy use by a family living in a city differ from energy use by a family camping in a forest?

In cities, electrical energy is used. In forest, people have to rely on solar energy etc.


How does energy used by a family living in a city differ from energy used by a family camping in a forest?

In cities, electrical energy is used. In forest, people have to rely on solar energy etc.


Which type of thermal energy transfer does not need particles to take place?

Radiation is the type of thermal energy transfer that does not require particles to take place. Radiation can occur through empty space and does not rely on the movement of particles like conduction and convection do.


What kind of heat transfer can happen between objects where there are no molecules?

Radiative heat transfer can occur between objects where there are no molecules. This type of heat transfer does not rely on the presence of a medium for energy transfer, as it involves the emission and absorption of electromagnetic radiation between objects at different temperatures.


Which type of wave can only transfer energy though a medium?

Mechanical waves can only transfer energy through a medium because they rely on the vibration and movement of particles in the medium to propagate. Sound waves are an example of mechanical waves that require a medium such as air, water, or solids to travel.


What machines use electrical energy?

Machines that use electrical energy include washing machines, refrigerators, air conditioners, computers, and televisions. These machines rely on electricity to function and perform their intended tasks.


WHAT KIND of energy does an alarm have?

An alarm typically uses electrical energy to power its components, such as the display, speaker, and internal circuitry. It may also rely on a battery as a backup power source in case of a power outage.


How do conductors and insulators transfer heat?

Conductors transfer heat through the movement of free electrons that can carry thermal energy efficiently. Insulators are poor conductors because they lack free electrons for heat transfer, so they rely on slower processes like molecular vibration and collisions for heat transfer to occur.


Red blood cells and the brain rely on what for energy?

They rely on glucose for energy.


What kind of waves disturb matter?

Mechanical waves, such as sound waves and seismic waves, disturb matter by causing particles in the medium to vibrate and transfer energy from one point to another. These waves require a medium to propagate, as they rely on the physical interaction between particles to transfer energy.