Electric Field

Front 1

A sphere of influence around a charge is what?

Back 1

An electric field.

Front 2

What does an electric field do?

Back 2

It is only felt by another charge.

Force coming from the sphere.

Stores energy of that charge.

Neutral objects will not be effected.

Front 3

What is always positive and very small?

Back 3

A test charge.

Front 4

How will any test charge be pushed away if it interacts with another positive charge?

Back 4

It will be pushed away in a straight line.

Front 5

If the other charge is negative, how will the test charge be effected?

Back 5

The test charge will be drawn to the negative charge in a straight line.

Front 6

Describe an electric field of an electric dipole.

Back 6

They are charges of an equal strength at a fixed distance that are not allowed to move.

Front 7

Describe parallel plates when it comes to charges

Back 7

Parallel plates with the same stress, separated by a fixed distance, one positive, one negative

Front 8

What is the formula between an electric field (vector), electric force (vector) and electric charge (vector).

Back 8

E (electric field) = Fe (electric force) / q (charge) or E = Fe/q

Front 9

Can both the electrostatic and the gravitational force be attractive or repulsive?

Back 9

Gravitational force is only attractive. Electrostatic can be attractive or repulsive

Front 10

If you have two charges, q1 and q2, with q1 = 3 microcoulombs and q2 = 2 microcoulumbs, with q0 = 4 microcoulumbs. q1 is 10cm from q0 while q2 is 20cm from q0.

A) what is the net electrical force?

B) what is the electric field at the location of charge q0 due to their two forces?

Back 10

A) Given force by q1 on q0 = 10.8N to the right and given force by q2 on q0 = 1.8N to the left, the net electric force (Fnet) is 10.8N - 1.8N = 9N to the right

B) E = Fnet/q0 = 9N/4microcoulombs = 2 * 25 * 10^6 N/C to the right. It is multiplied by 10^6 because you need it in Coulombs.

Front 11

Instead of saying positive or negative force when it comes to electric fields, what do you say?

Back 11

To the left for negative, to the right for positive.

Front 12

If the distance between two charged objects is doubled will the electrostatic force that one object exerts on the other be cut in half?

Back 12

No, it would become 1/4.

Front 13

If two charges are both doubled in magnitude without changing the distance between them, will the force that one exerts on the other be doubled?

Back 13

The force would go up by a factor of four because r²

Front 14

An election had a charge of -1.6*10^-19 C. How many electrons would be needed to produce a net charge of -8.0 * 10^-7?

Back 14

-8 * 10^-7/-1.6 * 10^-19 = (8/1.6)*10^¹²

Front 15

Two charged particles exert an electrostatic force of 27N on each other. What will the magnitude of the force be if the distance between the two particles is increased to three times the original distance?

Back 15

27/3² = 27/9 = 3

Front 16

A charge of +2 *10^-6 C is located 20 cm froma charge of -4 * 10^-6C

A) what is the magnitude of the force exerted on each charge?

B) on a drawing, indicate the directions of the forces acting on each charge.

Back 16

A) q1 = 2microcoulumbs

q2 = -4microcoulumbs

r = .2m

(2 * 10^-6 * -4 * 10^-6 * 9 * 10^ 9)/.2² = 1.8 (ignore the negative sign)

Front 17

A +1.5 * 10^-6 C test charge experiences forces from two other nearby charges: a 12N force due east and an 8N force due west. What are the magnitude and direction of the electric field at the location of the test charge?

Back 17

F = Kq1q2/r²

Fnet = 4N due east

E = Fnet/q = 4N/1.5*10^-6 = 2.6*10^6 to the right

Front 18

What is only felt by another charge coming from a sphere, and stores energy of a charge, that doesn't effect neutral charges?

Back 18

An electric field

Front 19

Can cm be used with Coulombs?

Back 19

No, you must convert it to meters.