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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.
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.
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.
Do the energy of a mechanical wave depends on the frequency of the wave?
Yes, energy transfer for mechanical waves is dependant on frequency as well as amplitude. Energy of electromagnetic waves, however, does not rely on frequency but solely on amplitude.
Red blood cells and the brain rely on what for energy?
They rely on glucose for energy.
What industries rely on biomass?
Fuel companies rely on this energy source to power things up. Automotive industries also rely on thin energy source(biomass).
Space satellites rely on this type of energy?
Solar energy
Do you rely on the suns energy?
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Which method of energy transfer does not involve the movement of matter?
Energy transfer takes place by convection (the movement of hot air or other fluids due to diferences in densiity), conduction (transfer of heat through contact - caused by collisions between adjacent particles), or radiation (the transfer of energy by electromagnetic waves such as light or infra-red rays).Radiation requires matter to create and absorb the EM waves, (i.e. you need a hot object to give off the IR waves) but the waves themselves can travel through a vacuum, so do not require matter to transfer energy.
What energy sources does Canada mostly rely on to produce energy?
water
Space satelites rely on this type of energy?
There's only one: -- In a receiving dish, the collected and focused electromagnetic energy changes to electrical energy in the feed, LNA, or LNB at the focus of the dish. -- In a transmitting dish, the electrical energy from the transmitter changes to electromagnetic energy, either at the focus of the dish if the transmitter is mounted there, or else some distance from the dish and then moved to the focus through a hollow 'waveguide'.
Why pine cones are not colorful?
because gymnosperms rely on the mass production of pollen and wind for pollen transfer and pollination. as insects play a relatively small roll in the transfer of pollen there is no necessity for the plant to expend energy on producing colourful cones (as is the case with angiosperms and flowers).
Is there anything on earth that does not rely on the sun?
All living things rely, ultimately, on the sun's energy.
