2a

Question 1

Difference between Speed and Velocity

Answer 1

Speed is how fast your going with no regard for direction. Velocity however must also have the direction specified.

Question 2

Distance-Time Graph equation

Answer 2

Speed= Distance x Time

Question 3

Formula for Acceleration

Answer 3

Change in velocity / Time taken

Question 4

Velocity-Time Graph, how to find Acceleration

Answer 4

Acceleration= gradient= vertical change/ horizontal change

Question 5

Difference between Weight and Mass

Answer 5

Mass is just the amount of stuff, weight is caused by the pull of the gravitational force.

Question 6

What is Mass measured in?

Answer 6

Kg

Question 7

What is Weight measured in?

Answer 7

Newtons

Question 8

Formula relating Mass, Weight and Gravity?

Answer 8

Weight= mass x gravitational field strength

Question 9

Define resultant force

Answer 9

Overall force on a point or an object

Question 10

How do you work out Resultant Force?

Answer 10

F=ma m=mass (kg) a=acceleration in metres per second squared F=the resultant force in Newtons (N)

Question 11

What is Terminal Velocity?

Answer 11

When falling objects first set off, the force of gravity is much more than the frictional force slowing them down, so they accelerate. As the speed increases the friction builds up. This gradually reduces the acceleration until eventually the frictional force is equal to the accelerating force and then it won’t accelerate anymore. It will have reached its maximum speed or terminal velocity and will fall at a steady speed.

Question 12

What two factors affect your stopping distance?

Answer 12

Thinking Distance and Braking Distance

Question 13

What two things affect your Thinking Distance?

Answer 13

How fast your going, how dopey you are

Question 14

What four things affect your Braking Distance?

Answer 14

How fast your going, how good your brakes are, how good the tyres are, how good the grip is

Question 15

What is the formula for Work Done?

Answer 15

Work Done= Force x Distance

Question 16

How do you work out somethings Gravitational Potential Energy?

Answer 16

= mass x g x height

g= gravitational field strength

Question 17

How do you work out somethings Kinetic Energy?

Answer 17

= 1/2 x mass x speed squared

Question 18

To stop a moving car, the energy is converted to…

Answer 18

heat energy as friction between the wheels and the brake pads, causing the temperature of the brakes to increase

Question 19

Extension of an Elastic Object is Directly Proportional to Force, the equation is…

Answer 19

Force= k (the spring constant, N/m) x e (extension, m)

Question 20

What is the limit of proportionality in springs?

Answer 20

The maximum force that the elastic object can take and still extend proportionally

Question 21

What is the equation for Power?

Answer 21

Power= Work Done (or energy transferred) / Time taken

Question 22

What is power measured in?

Answer 22

Watts or J/s

Question 23

Equation for Momentum

Answer 23

Momentum (kgm/s) = Mass (kg) x Velocity (m/s)

Question 24

Name five ways cars are designed to increase safety

Answer 24

Brakes, crumple zones, side impact bars, seat belts and air bags

Question 25

What is the build-up of static caused by?

Answer 25

Friction

Question 26

Explain Static Electricity

Answer 26

When certain insulating materials are rubbed together, negatively charged electrons will be scraped off one and dumped on the other. This will leave a positive static charge on one and a negative static charge on the other. Which way the electrons are transferred depends on the two materials involved. Electrically charged objects attract small objects placed near them.

Question 27

Two things with opposite electric charges are...

Answer 27

Attracted

Question 28

Two things with the same electric charges will...

Answer 28

Repel each other

Question 29

An example of a good conductor

Answer 29

Metal

Question 30

What is Current?

Answer 30

The flow of electric charge round the circuit. Current will only flow through a component if there is potential difference across that component. Unit= amperes (A)

Question 31

What is Potential Difference?

Answer 31

The driving force that pushes the current round. Unit= volts (V)

Question 32

What is Resistance?

Answer 32

Anything in the circuit which slows the flow down. Unit=ohm (Ω)

Question 33

The greater the resistance across a component the what the current that flows?

Answer 33

Smaller

Question 34

What is the equation for Current?

Answer 34

Current (A) = Charge (C)/ Time (s)

Question 35

What is the equation for Potential Difference?

Answer 35

P.D. (V) = Work Done (J) / Charge (C)

Question 36

Main facts about an Ammeter

Answer 36

Measures the current, must be placed in series, can't be put in parallel

Question 37

Main facts about an Voltmeter

Answer 37

Measures the potential difference across the component under test, must be placed in parallel around the component

Question 38

The current through a resistor is directly proportional

Answer 38

To potential difference

Question 39

As the temperature of a filament lamp increases the resistance...

Answer 39

Increases

Question 40

Current will only flow through a diode in...

Answer 40

One direction

Question 41

Does resistance increase or decrease with temperature?

Answer 41

Increase, when an electric charge flows through a resistor, some of the electrical energy is transferred to heat energy and the resistor gets hot. This heat energy causes the ions in the conductor to vibrate more. with the ions jiggling around its more difficult for the charge-carrying electrons to get through the resistor- the current can't flow as easily and the resistance increases.

Question 42

What is the equation linking Potential Difference, Current and Resistance?

Answer 42

Potential Difference= Current x Resistance

Question 43

What does the resistance of a Thermistor do as the temperature increases?

Answer 43

Decreases

Question 44

Key features of Series Circuits

Answer 44

Potential Difference is shared, Current is the same everywhere, Resistance adds up (the bigger the resistance of a component, the bigger its share of the total P.D.) and Cell Voltages add up

Question 45

Key features of Parallel Circuits

Answer 45

Potential Difference is the same across all components, Current is shared between branches