Flashcards in Electric Fields Deck (35)

Loading flashcards...

1

## What is an electric field associated to?

### Charge

2

## Define electric field strength

### The force that would act on a unit charge placed at a point in the field.

3

## What is the relationship between electric field strength and the distance?

### E ∝ 1/r^2

4

## What is the pattern of electric field lines?

### Radial

5

## What is the direction of an electric field?

### The direction of the force that would act on a positive charge placed in the field.

6

## Give two factors that can affect the size of the electric field between two plates.

###
- The pd across the plates.

- The plate separation.

7

## What is the relationship between electric field strength and the position between the plates?

### They are independent

8

## What is the relationship between electric field strength and the pd across the plates?

### E ∝ V

9

## What is the relationship between electric field strength and the separation of the plates?

### E ∝ 1/d

10

## When does the formula E=V/d apply?

### When two plates are parallel

11

## When does an electric field do work on a positive charge?

### When the charge moves in the direction of the electric field.

12

## What is the relationship between electric field lines and equipotential surfaces?

### They are perpendicular to each other.

13

## What is the relationship between field strength and potential?

### Field strength = -Potential gradient (-dV/dx)

14

## What is the relationship between potential and charge?

### V ∝ Q

15

## What is the relationship between potential and distance?

### V ∝ 1/r

16

## How is potential calculated?

### V = (1/4πε0)(Q/r)

17

## What is ε0?

### The permittivity of free space

18

## How is the potential at the surface of a sphere calculated?

### V = (1/4πε0)(Q/a)

19

## How is electrical potential energy calculated?

### EPE = qV

20

## What does a negative EPE show?

### An attractive system

21

## How is electric field strength in a radial field calculated?

### E = (1/4πε0)(Q/r^2)

22

## How is the force between two objects calculated?

### F = (1/4πε0)(Qq/r^2)

23

## Is field potential scalar of vector?

### Scalar

24

## Is field strength scalar or vector?

### Vector

25

## What is the unit of W?

### Joules

26

## When is work done by the field?

### When W is negative

27

## When is work done against the field?

### When W is positive

28

## How is work done calculated?

### W = qΔV

29

## How is the force on a charge in an electric field calculated?

### F = qE

30