Electricity Flashcards

Question

What is another type of circuit breaker?

Answer 1

Current x Voltage

Answer 2

energy is transferred

Answer 3

the energy transferred per unit charge passed

Answer 4

one joule per coulomb

Answer 5

electrons will leave one material and be attracted to the other, leaving a positive charge on one material and a negative charge on the other

Answer 6

Polythene rod + cloth duster: electrons move from the duster to the rod. The rod becomes negatively charged and the duster is left with an equal positive charge acetate rod + cloth duster: electrons move from the rod to the duster. The duster becomes negatively charged and the rod is left with an equal positive charge

Answer 7

Electrons (negatively charged) moving elsewhere - the loss of electrons

Answer 8

The gain of electrons

Answer 9

By connecting it to earth with a metal strap. The electrons flow down the strap to the ground if the charge is negative and flow up the strap from the ground if the charge is positive

Answer 10

The rate of flow of electrical charge

Answer 11

a spark jumps across the gap between it and earth

Answer 12

1. A gold-leaf electroscope has a metal disc connected to a metal rod, at the bottom of which are attached two think pieces of gold leaf 2. When a rod with a known charge is brought near to the disc of the electroscope, electrons will either be attracted to or repelled from the metal disc depending on the charge of the rod 3. This induces a charge in the metal disc, which in turn induces a charge in the gold leaves 4. Both the gold leaves will have the same charge, so they will repel each other causing them to rise 5. When the rod is taken away the gold leaves will discharge and fall again

Answer 13

1. suspend a rod with a known charge on a thread and see if there is repulsion or attraction when the rod you're testing is brought close to it 2. if there is an attraction, the test rod has the opposite charge to the suspended rod. If there is repulsion, then the test rod has the same charge as the suspended rod

Answer 14

to demonstrate electrostatic charges

Answer 15

a rubber belt moving around plastic rollers beneath a metal dome

Answer 16

electrons will move between your body and the dome, giving your body a charge. The human body conducts charge, and like charges repel, so the charges will spread out as much as possible throughout your body. The charge is strong enough to make your hairs repel each other and stand on end

Answer 17

1. tiny drops of ink are forced out of a fine nozzle, making them electrically charged. 2. the droplets are deflected as they pass between two metal plates. A voltage is applied to the plates: one is positive, the other negative 3. the droplets are attracted to the plate of the opposite charge and repelled from the plate with the same charge 4. the size and direction of the voltage across each plate changes so each droplet is deflected to hit a different place on the paper, making up the printout

Answer 18

1. The image plate is positively charged. An image of what you're copying is projected onto it 2. Whiter bits of what you're copying make light fall on the plate and the charge leaks away in those places 3. The charged bits attract negatively charges black powder which is transferred onto positively charged paper 4. The paper is heated so the powder sticks

Answer 19

Rain drops and ice bump together inside storm clouds, knocking off electrons and leaving the top of the cloud positively charged and the bottom of the cloud negatively charged. This creates a huge voltage and a big spark

Answer 20

As fuel flows out of a filler pipe, static can build up. This can easily lead to a spark and in dusty or fume places an explosion or fire. Solution: make the nozzles out of metal so that the charge is conducted away instead of building up. It's also good to have earthing straps between the fuel tank and the fuel pipe.

Electricity Flashcards

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