GCSE Physics Edexcel Higher Triple Paper 1 Content

Give the symbol and power of ten that mega denotes

Symbol is capital M. Power is 10^6

Give the symbol and power of ten that micro denotes

Symbol is the Greek letter mu - a bit like a u, with a long tail to the left. Power is 10^-6

Give the symbol and power of ten that giga denotes

Symbol is capital G. Power is 10^9

Give the symbol and power of ten that centi denotes

Symbol is lowercase c. Power is 10^-2

Give the symbol and power of ten that nano denotes

Symbol is lowercase n. Power is 10^-9

Give the symbol and power of ten that milli denotes

Symbol is lowercase m. Power is 10^-3

Give the symbol and power of ten that kilo denotes

Symbol is lowercase k. Power is 10^3

Convert 3 hours into seconds

3x60x60 = 10800 s

Convert 250 cm^3 into m^3

0.000250, or 2.50 x 10^-4

Convert 250 N/cm^2 into Pascals

2,500,000 or 2.50 x 10^6

How many significant figures should you use when quoting numerical answers

You should look at the data given to you. You need to use the least number of significant figures given to you. You are only as accurate as the least accurate piece of data.

Describe how to show a relationship is directly proportional using a table

Show that as one variable doubles the other doubles.

Describe how to show a relationship is directly proportional using a graph

If directly proportional the line should be straight AND through the origin.

Describe how to show a relationship is inversely proportional

As one variable doubles the other halves.

What is a systematic error

All data points are affected by the same amount. E.g. Scale has not been zeroed before use.

What is a random error

Only some data points are affected, or all data points are affected by a different amount. E.g. taking measurement from a fluctuating scale or multimeter.

How can you improve accuracy in time measurements

Using a longer time to reduce percentage uncertainty due to human reaction time. E.g. time over longer distance or for multiple rotations.

Give two ways in which measurements can be taken accurately

Measure at eyelevel to reduce parallax error; Repeat and average; Use an instrument with a higher resolution; Increase time so that human reaction time is a smaller percentage of the measurement; Record with a slow motion camera with ruler and timer in shot.

Explain the difference between a scalar quantity and a vector quantity and give examples of each

Scalar has magnitude (size) but no direction, e.g. speed or area. Velocity has magnitude AND direction e.g. velocity or weight

Give three examples of vector quantities

Velocity, acceleration, force, displacement, moments

How do you show that a vector quantity is in the opposite direction to another

To show a vector is in the opposite direction you can make it negative.

Give three examples of scalar quantities

Speed, distance, energy, time

Give 3 examples of vector quantities

Displacement, velocity, acceleration, force, weight, momentum

Why is circular motion at a constant speed still accelerating

Velocity is a vector and the direction is constantly changing therefore so is velocity. Acceleration is change in velocity over time so the object is accelerating since velocity is changing.

Define displacement

The shortest distance between the current and start position with a direction.

Define acceleration

Rate of change in velocity OR Change of velocity / time taken

What equation defines momentum?

mass x velocity

How is speed found from a distance-time graph?

gradient of the line using a big triangle.

How is instantaneous speed found from a graph at a time T?

Draw a tangent to the curve at time t as long as possible. Find the gradient of this tangent using a big triangle.

How do you find average speed?

Take total distance divided by total time.

How is acceleration found from a velocity-time graph?

gradient of the line

How is displacement found from a velocity-time graph?

area under the graph

How is a single light gate used to measure speed (include the equation the datalogger uses to calculate the speed)

the datalogger records the time for which the light gate is blocked. You will have previously measured and entered the length of the interrupt card. The datalogger then divides length of the card by time the light gate was blocked to calculate speed.

Describe how to determine speed in a lab

Measure distance with either metre ruler or tape measure (for longer distances). Measure the time with a stopwatch. Calculate the speed by doing distance/time.

Give a typical speed for wind, in m/s

0.5 m/s to 30 m/s (a very strong wind!)

Give a typical speed for sound in air in m/s

340 m/s

Give a typical speed for walking in m/s

1-2 m/s

Give a typical speed for running in m/s

3-10 m/s

Give a typical speed for cycling in m/s

3-15 m/s

Give a typical speed for a car in m/s

0-45 m/s

Give a typical speed for a train in m/s

5-50 m/s

What is the value of the acceleration of freefall, g, used for GCSE? (include units in your answer)

10 m/s2

What condition must be met to use the xuvat equations?

Acceleration is constant.

Give the four contact forces encountered at GCSE

Normal reaction (Between objects resting on a surface); Tension (An object being stretched or squashed); Friction (between moving objects in contact, always opposes motion); Air resistance (Due to collisions between air particles and a moving object)

Give the three non-contact forces encountered at GCSE.

Magnetic (experienced by a magnetic material in a magnetic field); Electrostatic (Experienced by a charged object in an electric field); Gravitational (Attraction between objects with mass)

State Newton's first law

An object will continue with a constant velocity (same speed and direction) unless acted on by a resultant force

State Newton's second law and give an equation in terms of momentum

if a resultant force acts on an object, it will accelerate in the direction of the force, force = change in momentum / time taken

State Newton's third law

if object A exerts a force on object B, object B will exert an equal and opposite force on object A. (Every action has an equal and opposite reaction)

What acronym helps you remember how to find a Newton's 3rd law pair.

TEDBOD, Type Equal Different Bodies Opposite Directions

What is the Newton's third law pair for the weight of a cat.

The cat pulls the Earth Up (Since the original force is Earth pulls cat down)

Explain why a Newton's 3rd law pair can't cancel each other out?

They act on different bodies

A book is at rest on a table as the weight force acting on it and the reaction force from the table are equal. Explain why these two forces are not a third law pair.

They act on the same body (the book) and they are different types of force. (weight and contact force)

What equation links mass, force and acceleration?

Fnet = ma

What equation links mass, weight and gravitational field strength?

W=mg *mass must be in kg

What is the difference between mass and weight?

Mass is a measure of the amount of matter in an object measured in kg, it is a scalar. Weight is the force due to gravity and measured in Newtons, it is a vector. Weight changes depending on the gravitational field strength whereas mass does not.

How can the weight of an object be measured?

Hang the object from a force meter/newton meter

What is the centripetal force?

Resultant force towards the centre of a circle.

Explain why an object moving in a circular orbit can be accelerating whilst its speed remains constant.

Acceleration is the rate of change in velocity. Velocity is a vector and since it is constantly changing direction, the velocity is constantly changing so the object accelerates.

Give an example of an object moving in a circle and what provides the centripetal force.

Car turning (Friction); Hammer throw (Tension); Planet orbiting (Gravitational force)

How is inertial mass defined?

Inertial mass = resultant force/acceleration (inertia is the reluctance of an object to change its motion)

An object with no resultant force will ...

Either continue at constant speed or remain stationary.

An object with a resultant force in the same direction as the motion will ...

Accelerate

An object with a resultant force opposing its motion will ...

Decelerate.

Explain why the acceleration of a rocket increases as it ascends.

Fnet = ma -> a = Fnet/m ; As the rocket is further from the earth the weight force downwards decreases so the fret increases and so does acceleration. As the rocket burns more fuel the mass of the rocket decreases so the acceleration increases.

Explain why the ramp must be tilted slightly in the Newton's 2nd Law core practical?

This to compensate for friction. This is so that the trolley will travel at a constant speed down the ramp when no force is applied.

What is the definition of terminal velocity?

Constant speed reached by an object in freefall when weight = drag

Explain the effect of speed on air resistance.

An increase in speed increases the frequency of collisions with air particles and therefore the air resistance increases.

Explain the effect of surface area on air resistance.

As surface area increases the frequency of collisions with air particles increases and therefore the air resistance increases.

Explain what happens to the forces and motion of a parachute jumper just after they jump out of the plane and start falling but have not opened their parachute yet.

When the parachute jumper has just jumped they are not moving yet so have no air resistance. The only force acting is weight which is equal to their resultant force so they fall with an acceleration of 10 m/s2. As they speed up, the air resistance increases so the resultant force decreases, this decreases the acceleration. They are still getting faster but at a decreasing rate.

Explain what happens to the forces and motion of a parachute jumper just after they open their parachute and continue to fall until they reach terminal velocity.

When the jumper opens their parachute, the surface area increases which increases the air resistance upwards so that it is greater than the weight. The jumper is moving downwards but had a resultant force is upwards so they decelerate. As they get slower, the air resistance decreases so the fret decreases and therefore the deceleration decreases. They slow down until they reach a new lower terminal velocity where weight = air resistance and the fret and acceleration equal zero.

Define momentum.

mass x velocity , it is a vector quantity measured in kgm/s

Give a method for measuring human reaction times.

Have a computer screen that changes colour and then click on a mouse to register the change, timing how long this takes OR drop a ruler in between the first finger and thumb. The reaction time can be calculated from the distance the ruler has dropped

Define thinking distance, braking distance and stopping distance.

Thinking distance - the distance travelled whilst the driver reacts; the braking distance - the distance travelled by the vehicle from the moment the brakes are applied until the vehicle stops; the stopping distance = thinking distance + braking distance

Explain why a lorry takes longer to come to a stop from 70 mph than a car under the same braking force.

As stated in Newton's 2nd Law the resultant force is directly proportional to the rate of change in momentum. The lorry has a larger inertial mass and therefore a larger change in momentum. Since Fnet is the same, the lorry will take longer to stop.

Give 2 factors that affect the thinking distance

speed, tiredness of driver, distractions, alcohol, drugs etc

Give 3 factors that affect the braking distance

mass, speed, condition of the brakes, road or tyres etc

Explain what happens to the speed of a car when a driver sees a hazard and performs an emergency stop.

The driver takes time to react to the hazard and hasn't pressed the brakes yet so the car continues at the original constant speed. The driver then presses the brakes with a large constant force giving a large constant deceleration until it the car comes to a stop.

If velocity doubles the braking distance ...

quadruples as x is proportional to v squared.

If mass doubles the braking distance ...

doubles as x is directly proportional to mass

If braking force doubles the braking distance ...

halves as x is inversely proportional to force

If velocity doubles the thinking distance ...

doubles as distance = speed x time

If mass doubles the thinking distance ...

Nothing, Mass is independent of thinking distance.

If braking force doubles the thinking distance ...

Nothing, the driver hasn't started braking yet.

Explain how a seatbelt reduces risk of injury in a car crash.

A passenger will continue moving forward in a car crash due to Newton's first law. There is no resultant force on the person so they carry on moving at a constant velocity and could hit their head on the dashboard. Fnet = (mv-mu)/t ; Since the dashboard is hard the time for the person to stop will be small so the force is very large which would cause injury such as broken bones. A seatbelt provides a resultant force backwards to stop the passenger. It stretches during the collision to increase the time it takes to stop the passenger and so reduces the rate of change of momentum and therefore force on the passenger.

Explain how an airbag reduces risk of injury in a car crash.

A passenger will continue moving forward in a car crash due to Newton's first law. There is no resultant force on the person so they carry on moving at a constant velocity and could hit their head on the dashboard. Fnet = (mv-mu)/t ; Since the dashboard is hard the time for the person to stop will be small so the force is very large which would cause injury such as broken bones. An airbag is soft so will squash and provide a resultant force backwards on passenger to slow them down. As it deforms it increases the time it takes to stop the passenger and so reduces the rate of change of momentum and therefore force on the passenger.

Explain how a crumple zone decreases the risk of injury in a car crash.

A passenger will continue moving forward in a car crash due to Newton's first law. There is no resultant force on the person so they carry on moving at a constant velocity and could hit their head on the dashboard. Fnet = (mv-mu)/t ; Since the dashboard is hard the time for the person to stop will be small so the force is very large which would cause injury such as broken bones. The crumple zone deforms during the crash which increase the time taken to stop and therefore the rate of change in momentum which reduces the force on the vehicle and passengers.

Give the 8 stores of energy required for GCSE

Magnetic, Thermal, Chemical, Kinetic, Electrostatic, Elastic potential, Gravitational potential, Nuclear

Give the energy transfers required for GCSE.

Mechanical work, Electrical work, Heating, Radiation

Describe an experiment to measure the gravitational potential energy gained by an object as it is lifted by a motor.

Measure the mass of the object with a mass balance. Measure the change in height with a ruler. Measure the initial and final heights reached using the bottom of the object as a reference point. Clamp the ruler and use a set square to ensure the ruler is upright. Calculate the gpe by using the equation gpe = mg(change in h)

Describe an experiment to measure the kinetic energy gained by rolling a trolley down a ramp.

Measure the mass of the trolley using a mass balance. Put an interrupt card on the trolley and measure the length using a metre rule, input this value to the data logger. Roll the trolley down a ramp so that it passes through a light gate connected to a data logger at the end. The light gate will calculate speed = length of interrupt card/time the light beam is blocked. Then use this in the equation KE = 1/2mv^2

Explain what is meant by the conservation of energy?

Energy cannot be created or destroyed, it is just transferred between different energy stores

What are the energy transfers for an object projected upwards or up a slope

kinetic energy to GPE via work done against gravity.

What are the energy transfers for an object that is falling.

GPE to kinetic energy via work done by gravity.

What are the energy transfers for a moving object hitting an obstacle

kinetic energy to thermal store of object and surroundings via heating

What are the energy transfers for an object being accelerated by a constant force

mechanical (work done by force) to kinetic energy

What are the energy transfers for a vehicle slowing down

kinetic energy to thermal store of the brakes and surroundings (via frictional force)

What are the energy transfers for bringing water to a boil in an electric kettle

electrical working to thermal store of water (and thermal store of surroundings and kettle)

What is meant by energy dissipating?

Energy spreads out and becoming less useful (usually when energy is transferred to the surroundings)

How is energy often dissipated?

Heat loss to the surroundings, Work done against air resistance, Work done against friction.

A tennis ball is dropped, why will it not bounce above the point it was released.

Energy is conserved, the GPE at the end cannot be more than at the start so will not reach a higher height.