OCR A-Level Physics Paper 1

What is the value of the prefix T (tera)

10¹²

What is the value of the prefix G (giga)

10⁹

What is the value of the prefix M (mega)

10⁶

What is the value of the prefix k (kilo)

10³

What is the value of the prefix d (deci)

10⁻¹

What is the value of the prefix c (centi)

10⁻²

What is the value of the prefix m (milli)

10⁻³

What is the value of the prefix μ (micro)

10⁻⁶

What is the value of the prefix n (nano)

10⁻⁹

What is the value of the prefix p (pico)

10⁻¹²

What six base units of the SI system are used in A Level Physics?

metre, kilogram, second, Ampere, Kelvin, Mole

What six base quantities of the SI system are used in A Level Physics?

length, mass, time, electric current, absolute temperature, amount of substance.

What is the base unit of mass?

kg

What is the base unit of length?

m

What is the base unit of time?

s

What is the base unit of current?

A

What is the base unit of absolute temperature?

K

What is the Unit of potential difference?

V

What are the Units of density?

kgm⁻³

What is the SI unit of energy?

J

What is the SI unit of power?

W

What is the SI unit of charge?

C

What units are equivalent to the volt?

JC⁻¹

What base units are equivalent to the Newton?

kgms⁻²

What base units are equivalent to the Joule?

kgm²s⁻²

What units are equivalent to the Pascal?

Nm⁻²

What are the units of momentum?

kgms⁻¹

What are the units of resistivity?

Ωm

What units are equivalent to a Watt?

Js⁻¹

What are the units of angular velocity (ω)?

rad. s⁻¹

What is 1m² in mm²?

10⁶mm²

What is 1m³ in cm³?

10⁶cm³

What is 1km² in m²?

1x10⁶m²

What is 1cm³ in mm³?

10³mm³

There are 10²⁴ free charge carriers per m³ of a material. How many are there per mm³?

10¹⁵

10⁶ particles strike each mm² of a surface per second. How many strike 1m² of the surface per second?

10¹²

If there is 1 particle per mm³, how many are there per m³?

10⁹

Water has a density of 1000kgm⁻³. What is this in kgcm⁻³?

10⁻³

Water has a density of 1000kgm⁻³. What is this in gcm⁻³?

1

What is a control variable?

Something that must be kept constant to prevent it affecting the dependent variable

What is meant by the repeatability of results?

Similar results would be obtained from repeats of the same measurement from the same experimental set up.

What is meant by the reproducibility of results

Similar results would be obtained from repeats by different people with different equipment.

How can you ensure a metre rule is held vertically?

Use a plumb line, set square or spirit level

How do you avoid parallax error?

Ensure eye, object and scale are all in line with each other OR ensure object and scale are directly adjacent to each other

What is meant by the term random error?

Errors that cause the measurement to vary in unpredictable ways.

What is a systematic error?

An error that causes the measurements to differ from the true value by a consistent amount.

What is a zero error?

An error that occurs due to the measuring instrument reading a non-zero reading when the measured quantity is zero.

What is meant by the accuracy of a result?

How close a measurement is to the 'true' or accepted value

What is meant by the precision of results?

How close repeated measurements are to each other.

What is meant by the resolution of a measuring instrument?

The smallest change in quantity that can be measured.

What determines the resolution when using a multimeter?

The scale selected.

What is the resolution of a metre rule?

1mm

What is the resolution of vernier calipers?

0.1mm

What is the resolution of a micrometer

0.01mm

How do you find the absolute uncertainty from repeated readings?

± ½ the range of the repeats

How do you estimate uncertainty when repeated results are identical?

± ½ the resolution of the instrument

How do you calculate percentage uncertainty?

(Absolute uncertainty ÷ 'calculated OR measured' value) × 100

What do you do to the uncertainties when quantities are added or subtracted?

The absolute uncertainties are added together

What do you do to the uncertainties when quantities are multiplied or divided?

The percentage uncertainties are added together

What do you do to the uncertainties when a quantity is raised to a power?

The percentage uncertainty is multiplied by that power

How do you find the uncertainty in a gradient?

± (gradient of the line of best fit − gradient of the line of worst fit)

What is a line of worst fit?

The steepest or shallowest line that passes through the error bars.

What are error bars?

Lines to show the range of the absolute uncertainty of each data point on a graph

How do you find uncertainty in a y-intercept?

± (y-intercept of the line of best fit − y-intercept of the line of worst fit)

What is a scalar quantity?

A quantity with magnitude but no direction.

What is a vector quantity?

A quantity with magnitude and direction.

When adding two perpendicular vectors what can you use to find the direction of the resultant?

Trigonometry

When adding two perpendicular vectors what can you use to find the magnitude of the resultant?

Pythagoras' Theorem

What is vector resolution?

The process of splitting a vector into two perpendicular components.

What is a resultant vector?

The sum of two or more individual vectors.

How is the resultant found in a vector diagram when adding several vectors together?

Join the vectors nose to tail and the resultant is from the tail of the first to the nose of the last vector.

What is displacement?

The distance of an object from a point in a specific direction (vector)

What is velocity?

Rate of change of displacement (vector) ∆s/∆t if constant

What is speed?

Change in distance traveled per unit time (scalar)

What is acceleration?

Rate of change of velocity (vector) ∆v/∆t if constant

What are the units of acceleration?

ms⁻²

What is meant by constant velocity?

Speed and direction of motion don't change

What is represented by the gradient of a distance-time graph?

Speed

What is represented by the gradient of a displacement-time graph?

Velocity

What is represented by the gradient of a velocity-time graph?

Acceleration

What is represented by the area under a velocity-time graph?

Change in displacement

What is represented by the area under an acceleration-time graph?

Change in velocity

When can the suvat equations by used?

When there is constant acceleration and motion along a straight line.

What is the effect of mass on the acceleration for an object in free-fall?

None

What is the relationship between displacement and time for an object falling freely from rest?

Displacement is proportional to time squared (sαt²)

What is a projectile

An object acted upon only by the force of gravity

What shape is the path of a projectile?

Parabolic

What is the initial vertical velocity of an object projected horizontally?

Zero

What angle of projection that results in maximum range

45°

Ignoring air resistance what is the acceleration of a projectile?

Always g downwards

How does horizontal velocity vary in projectile motion?

It is constant

How do the initial and final velocities compare if a projectile returns to its starting height?

They have the same magnitude but opposite direction/sign.

What equation used for the horizontal component of projectile motion?

Displacement = Velocity x time (since horizontal velocity is constant)

What aspect links the vertical and horizontal motion of a projectile

Time taken to fall

Why can SUVAT equations can be used for the vertical component of projectile motion

Since the motion is in a single direction with a constant acceleration

What is the vertical velocity at the peak of projectile motion?

Zero

What is the centre of mass of an object?

The point at which the weight can be assumed to act.

What does the weight of an object depend on?

It's mass and the gravitational field strength (W=mg)

What is a free-body diagram?

It is a diagram showing the set of forces acting on a single object.

What is weight?

The force due to gravity that acts through an objects centre of mass.