13.2 More about resistance

Question 1

what is the total potential resistance of 2 resistors in series

Answer 1

V=I(r1+r2)

Question 2

what is the total resistance of resistors in series equal to

Answer 2

the sum of the individual resistances

Question 3

equation for resistors in parallel

Answer 3

1/r = 1/r1 +1/r2

Question 4

what is the heating effect of an electric current due to

Answer 4

the resistance of the component

the charge carriers repeatedly collide with the positive ions of the conducting metal. There is a net transfernof energy due to this.

Question 5

what happens after a charge carrier loses kinetic energy in a collision

Answer 5

the force due tp the pd across the metal accelerates it until it collides with anther positive ion

Question 6

power =

Answer 6

iv or I^2r or v^2/r

Question 7

energy transferred per second to the component as thermal energy equals

Answer 7

I^2 r

Question 8

if the component is at a constant temperature what happens

Answer 8

heat transfer to the surroundings takes place at the same rate

therefore the rate of heat transfer = I^2 r

Question 9

a component heats up, what does this temperature rise depend on

Answer 9

The power supplied to it p = I^2r

the rate of heat transfer to the surroundings

Question 10

the energy transferred to the object by the electric current in time t

Answer 10

= power x time or = I^2 r t

Question 11

what does the energy transfer per second ro the component not depend on

Answer 11

the direction of the current