Paper 1 AS electricity

Question 1

what is the relationship between length of wire and resistance

Answer 1

directly proportional, as length increases so does resistance

Question 2

What is Newtons 3rd Law

Answer 2

for every force, there is an equal and opposite force

Question 3

what is Newtons 2nd law

Answer 3

F=Ma

Question 4

what is Newtons 1st law

Answer 4

law of inertia, an object at rest will stay at rest and an object in motion will stay in motion unless acted upon by an unbalanced force

Question 5

what is the relationship between tension and angles

Answer 5

As the angle decreases, the tension increases. This is known as the cosine of the angle, as the angle decreases the cosine value increases resulting in higher tension.

Question 6

what increases as the temperature of a metallic conductor increases

Answer 6

the amplitude of vibrations of the lattice ions

Question 7

what happens in an inelastic collision

Answer 7

momentum is conserved but kinetic energy is not

Question 8

why are safety features in cars related to momentum?

Answer 8

they increase the time taken for the momentum to change

Question 9

what is a couple

Answer 9

equal and opposite coplanar forces

Question 10

why shouldn’t lots of people stand on top of a bus?

Answer 10

the centre of mass will be higher and therefore a smaller tilt is required to move the buss’ centre of mass over the busses wheels

Question 11

what is work done measured in

Answer 11

joules

Question 12

what happens if force is perpendicular to the movement

Answer 12

no work is done

Question 13

what is the area underneath a force - distance graph

Answer 13

work done

Question 14

what is current

Answer 14

the rate of flow of charge

Question 15

what is kirchoffs first law

Answer 15

the total current arriving at a junction is equal to the total current

Question 16

what is the elementary charge

Answer 16

1.6 x 10^-19

Question 17

why would it be dangerous to fire bullets upwards on the moon but not so much on earth

Answer 17

energy is conserved, it will be converted into GPE but back into KE at the same speed, there is no air resistance to convert into heat

Question 18

explain the variation of resistance with potential difference for the filament bulb in terms of particle behaviour

Answer 18

as the voltage increases, the energy of electrons will also increase there will be a greater amount of collisions and therefore the temperature will increase. The amplitude of vibrations increase. Due to the increase of R the current does not increase in proportion

Question 19

what are the units of a moment

Answer 19

Nm

Question 20

do doors open easier when we push closer or further away

Answer 20

far away, the moment will be bigger

Question 21

what is the centre of mass

Answer 21

a point through which an objects weight seems to act

Question 22

what happens to an object if its centre of mass is outside its base

Answer 22

it will topple

Question 23

when will an object fall off a surface

Answer 23

when its centre of mass is not above its surface