PHYSICS A LEVEL OCR EXAM WITH QUESTIONS AND ANSWERS (100% SOLVED)
Describing the motion of an object falling in presence of drag - ✔✔✔–object falling in presence of drag
· When t=0 v=0 FN = mg a=g
· When t>0 v>0 FN = mg -D a< g
· When t>>0 v>>0 FN = mg -D a<< g
· Terminal Velocity reached when D=mg FN = mg -D = 0 a=0
Acceleration due to g PAG
Manual Method
Electronic Method - ✔✔✔–Acceleration due to g PAG
Manual Method
· Drop ball from different height and time taken to fall.
· Measure height with ruler and time with stopwatch
· Repeat to identify and remove anomalies
· Draw graph of 2s against T2 Gradient is and hence g
Electronic Method
· Light gates linked to data logger
· Enter length of interrupt card - Drop and record acceleration shown by data logger - Repeat
· Try again with Double data logger but a SINGLE light gate. Enter length of the interrupt part of card
Generic model for an LAQ about an investigation - ✔✔✔–Generic model for an LAQ about an
investigation
· State what you will change and what you will measure.
· State the equipment you will to measure both variables
· State the equation that links them
· Rearrange to give the quantity needed.
· If graph if required state what is on each axis and what the gradient will represent (generally all
constants left in gradient)
,PHYSICS A LEVEL OCR EXAM WITH QUESTIONS AND ANSWERS (100% SOLVED)
· Describe how to calculate quantity from gradient
· List some limitations to accuracy (If asked)
· Suggest solutions to said limitations
· Describe associated hazard (if asked)
· Suggest precautions to said limitations
Using Oscilloscope to measure Frequency - ✔✔✔–Oscilloscope to measure frequency
· Use sig. generator/tuning fork with mic and CRO
· Use loudest amplitude sound possible
· Adjust time base to get largest trace possible
· Adjust volts/div to get largest amplitude
· Multiply MS/div by number of divisions to get period - Frequency = 1/T
Using harmonic in tube to measure speed of sound - ✔✔✔–Harmonic in resonance tube to measure
speed
· Bucket of water, tube, mic and CRO
· Raise tube until first instance that amplitude increase
· As is first harmonic tube length =
· Measure height of tube with ruler
· Speed = 4 x tube length x frequency (see above)
Describing an experiment to determine an object's center of mass - ✔✔✔–Determine center of mass
· Hang shape on pin so it can freely rotate
· Hang plumb line off pin.
· Draw line along plumb line
· Rotate object and repeat
· Where lines intersect is center of mass
Young's Modulus PAG - ✔✔✔–Young's Modulus PAG
, PHYSICS A LEVEL OCR EXAM WITH QUESTIONS AND ANSWERS (100% SOLVED)
· Measure diameter of wire (with micrometer/calipers) in 3 places and calculate mean. Hence calculate A
· Run wire over pulley (to reduce friction)
· Clamp wire between two blocks
· Add marker on wire nearer to pulley end
· Measure original length (from blocks to marker) Add masses to hanger on loop - calculate
· Measure extension - calculate
· Draw graph of stress over strain. Draw LOBF
· YM is gradient of linear section only
Techniques used to measure motion of objects - ✔✔✔–Techniques used to measure motion of objects
· Light gates and data logger
· To reduce effect of friction, raise track at one end or use air track.
Techniques used to measure collisions of objects. - ✔✔✔–Techniques used to measure collisions of
objects
· Trolleys with springs
· Interrupt card on trolleys - enter value into data logger
· Light gates and data logger
· Place trolleys between light gates - compress springs.
· Start data logger and Trigger release mechanisms
Demonstrating/Explaining interference patterns - ✔✔✔–Demonstrating/Explaining interference
patterns
Use appropriate detector to measure intensity/amplitude
Maxima = highest intensity, constructive interference, in phase, path difference = n, Phase difference =
even integer of π
Minima = lowest intensity, destructive interference, in antiphase, path difference = odd integer, Phase
difference = odd integer of π
I-V Characteristics PAG - ✔✔✔–I-V Characteristics PAG
Describing the motion of an object falling in presence of drag - ✔✔✔–object falling in presence of drag
· When t=0 v=0 FN = mg a=g
· When t>0 v>0 FN = mg -D a< g
· When t>>0 v>>0 FN = mg -D a<< g
· Terminal Velocity reached when D=mg FN = mg -D = 0 a=0
Acceleration due to g PAG
Manual Method
Electronic Method - ✔✔✔–Acceleration due to g PAG
Manual Method
· Drop ball from different height and time taken to fall.
· Measure height with ruler and time with stopwatch
· Repeat to identify and remove anomalies
· Draw graph of 2s against T2 Gradient is and hence g
Electronic Method
· Light gates linked to data logger
· Enter length of interrupt card - Drop and record acceleration shown by data logger - Repeat
· Try again with Double data logger but a SINGLE light gate. Enter length of the interrupt part of card
Generic model for an LAQ about an investigation - ✔✔✔–Generic model for an LAQ about an
investigation
· State what you will change and what you will measure.
· State the equipment you will to measure both variables
· State the equation that links them
· Rearrange to give the quantity needed.
· If graph if required state what is on each axis and what the gradient will represent (generally all
constants left in gradient)
,PHYSICS A LEVEL OCR EXAM WITH QUESTIONS AND ANSWERS (100% SOLVED)
· Describe how to calculate quantity from gradient
· List some limitations to accuracy (If asked)
· Suggest solutions to said limitations
· Describe associated hazard (if asked)
· Suggest precautions to said limitations
Using Oscilloscope to measure Frequency - ✔✔✔–Oscilloscope to measure frequency
· Use sig. generator/tuning fork with mic and CRO
· Use loudest amplitude sound possible
· Adjust time base to get largest trace possible
· Adjust volts/div to get largest amplitude
· Multiply MS/div by number of divisions to get period - Frequency = 1/T
Using harmonic in tube to measure speed of sound - ✔✔✔–Harmonic in resonance tube to measure
speed
· Bucket of water, tube, mic and CRO
· Raise tube until first instance that amplitude increase
· As is first harmonic tube length =
· Measure height of tube with ruler
· Speed = 4 x tube length x frequency (see above)
Describing an experiment to determine an object's center of mass - ✔✔✔–Determine center of mass
· Hang shape on pin so it can freely rotate
· Hang plumb line off pin.
· Draw line along plumb line
· Rotate object and repeat
· Where lines intersect is center of mass
Young's Modulus PAG - ✔✔✔–Young's Modulus PAG
, PHYSICS A LEVEL OCR EXAM WITH QUESTIONS AND ANSWERS (100% SOLVED)
· Measure diameter of wire (with micrometer/calipers) in 3 places and calculate mean. Hence calculate A
· Run wire over pulley (to reduce friction)
· Clamp wire between two blocks
· Add marker on wire nearer to pulley end
· Measure original length (from blocks to marker) Add masses to hanger on loop - calculate
· Measure extension - calculate
· Draw graph of stress over strain. Draw LOBF
· YM is gradient of linear section only
Techniques used to measure motion of objects - ✔✔✔–Techniques used to measure motion of objects
· Light gates and data logger
· To reduce effect of friction, raise track at one end or use air track.
Techniques used to measure collisions of objects. - ✔✔✔–Techniques used to measure collisions of
objects
· Trolleys with springs
· Interrupt card on trolleys - enter value into data logger
· Light gates and data logger
· Place trolleys between light gates - compress springs.
· Start data logger and Trigger release mechanisms
Demonstrating/Explaining interference patterns - ✔✔✔–Demonstrating/Explaining interference
patterns
Use appropriate detector to measure intensity/amplitude
Maxima = highest intensity, constructive interference, in phase, path difference = n, Phase difference =
even integer of π
Minima = lowest intensity, destructive interference, in antiphase, path difference = odd integer, Phase
difference = odd integer of π
I-V Characteristics PAG - ✔✔✔–I-V Characteristics PAG
