OCR A LEVEL PHYSICS ,OCR A-LEVEL PHYSICS
REAL EXAM WITH QUESTIONS AND ANSWERS
[ALREADY GRADED A+}
impedance matching - ANS✔✔---use of two substances of similar acoustic
impedances to minimise reflection of ultrasound at the boundary between them
activity - ANS✔✔---rate at which nuclei in a radioactive source decay, measured in
becquerels
alpha radiation - ANS✔✔---ionising radiation consisting of particles resembling a helium
nucleus with a charge of +2e
air resistance - ANS✔✔---resistive force experienced by objects moving through air
ammeter - ANS✔✔---device used to measure electric current placed in series, ideally
has zero resistance
What's a physical quantity? - ANS✔✔---A physical property that can be measured or
quantified
,- Made up of a magnitude (value) and appropriate units
Prefix for 10^12 - ANS✔✔---Tera, T
Prefix for 10^9 - ANS✔✔---Giga, G
Prefix for 10^6 - ANS✔✔---Mega, M
Prefix for 10^3 - ANS✔✔---Kilo, k
Prefix for 10^-1 - ANS✔✔---Deci, d
Prefix for 10^-2 - ANS✔✔---Centi, c
Prefix for 10^-3 - ANS✔✔---Mili, m
Prefix for 10^-6 - ANS✔✔---Micro, μ
Prefix for 10^-9 - ANS✔✔---Nano, n
Prefix for 10^-12 - ANS✔✔---Pico, p
What is an estimate? - ANS✔✔---An educated guess at an answer
, What is a random error? - ANS✔✔---An error caused by unknown, unpredictable
changes during an experiment. Human error (e.g. misreading) is also a random error - can
lead to inconsistencies when repeating
Examples of random errors? - ANS✔✔---E.g. fluctuations in light or temperature
What is a systematic error? - ANS✔✔---An error involving the measuring equipment.
Often present in all readings taken, and can be removed once identified.
- Systematic errors tend to shift all the points in the same direction
Example of a systematic error? - ANS✔✔---E.g. equipment not used or calibrated
properly
S.I. unit and symbol for mass? - ANS✔✔---Kilogram, kg
S.I. unit and symbol for length? - ANS✔✔---Metre, m
S.I. unit and symbol for time? - ANS✔✔---Second, s
S.I. unit and symbol for temperature? - ANS✔✔---Kelvin, K
S.I. unit and symbol for electrical current? - ANS✔✔---Ampere, A
S.I. unit and symbol for amount of substance? - ANS✔✔---Mole, mol
S.I. unit and symbol for luminous intensity? - ANS✔✔---Candela, Cd
REAL EXAM WITH QUESTIONS AND ANSWERS
[ALREADY GRADED A+}
impedance matching - ANS✔✔---use of two substances of similar acoustic
impedances to minimise reflection of ultrasound at the boundary between them
activity - ANS✔✔---rate at which nuclei in a radioactive source decay, measured in
becquerels
alpha radiation - ANS✔✔---ionising radiation consisting of particles resembling a helium
nucleus with a charge of +2e
air resistance - ANS✔✔---resistive force experienced by objects moving through air
ammeter - ANS✔✔---device used to measure electric current placed in series, ideally
has zero resistance
What's a physical quantity? - ANS✔✔---A physical property that can be measured or
quantified
,- Made up of a magnitude (value) and appropriate units
Prefix for 10^12 - ANS✔✔---Tera, T
Prefix for 10^9 - ANS✔✔---Giga, G
Prefix for 10^6 - ANS✔✔---Mega, M
Prefix for 10^3 - ANS✔✔---Kilo, k
Prefix for 10^-1 - ANS✔✔---Deci, d
Prefix for 10^-2 - ANS✔✔---Centi, c
Prefix for 10^-3 - ANS✔✔---Mili, m
Prefix for 10^-6 - ANS✔✔---Micro, μ
Prefix for 10^-9 - ANS✔✔---Nano, n
Prefix for 10^-12 - ANS✔✔---Pico, p
What is an estimate? - ANS✔✔---An educated guess at an answer
, What is a random error? - ANS✔✔---An error caused by unknown, unpredictable
changes during an experiment. Human error (e.g. misreading) is also a random error - can
lead to inconsistencies when repeating
Examples of random errors? - ANS✔✔---E.g. fluctuations in light or temperature
What is a systematic error? - ANS✔✔---An error involving the measuring equipment.
Often present in all readings taken, and can be removed once identified.
- Systematic errors tend to shift all the points in the same direction
Example of a systematic error? - ANS✔✔---E.g. equipment not used or calibrated
properly
S.I. unit and symbol for mass? - ANS✔✔---Kilogram, kg
S.I. unit and symbol for length? - ANS✔✔---Metre, m
S.I. unit and symbol for time? - ANS✔✔---Second, s
S.I. unit and symbol for temperature? - ANS✔✔---Kelvin, K
S.I. unit and symbol for electrical current? - ANS✔✔---Ampere, A
S.I. unit and symbol for amount of substance? - ANS✔✔---Mole, mol
S.I. unit and symbol for luminous intensity? - ANS✔✔---Candela, Cd
