ATP - Accuracies Flashcards
To produce more accurate or reliable results
Repeat experiment, to calculate average reading.
Avoiding parallax error, look perpendicular to the ruler.
If accuracy in measurement was asked, check for zero error.
To draw an image created from lens
Inverted from the original object.
Sides are multiplied by the magnification.
Centre of mass experiment (with the lamina)
you view the string directly in front of card.
Minimizing heating effect of a current
Lower current
Increase voltage
Add a lamp
Increase resistance of a resistor
To increase accuracy of ray diagrams
View bases of pins since pins may not be vertical
Keep pins further apart and use more pins
Avoid parallax, explain action and reason
Repeats and average
Improvement made to experiments about heating/cooling effect and insulation
Same initial temperature.
Same volume of water.
Same shape and type of beaker.
Same room temperature.
Stirring the water in the beakers.
Record max. temperature
Heat loss could be reduced by
Insulation of beaker.
Covering beaker with a lid.
How to check if a rule is vertical
Use of set square or protractor
Plumb line
Spirit Level
Precautions taken in experiments about formation of images by a lens
Use a darkened area
Object and lens same height on bench
Take more readings
Avoiding parallax error in measurement, and look perpendicular to the ruler.
Object/lens/screen perpendicular to bench
Variables in experiments about springs and stretching effect
Number of coils
Length of spring
Diameter\thickness of spring or wire
Selection of loads
Improvement made to calculating circumference by string method
Avoid parallax error
Repeats and average
Thinner string
Parallel winding of springs
Precautions for circuit readings of I and V so that accurate
For I specifically:
Limit current so that temp. doesn’t increase
Use a tapping meter
For I and V: Switch off between readings.
Fair test for pendulum experiments
Length of pendulum
Shape of bob
No. of swings
Amplitude
Precautions and procedures in electrical experiments
Check for a zero error
Tap the meter to avoid sticking
Initially choose the highest range for the ammeter/voltmeter, then reduce the range for the ammeter so that the deflection is almost full scale
Always check polarities before closing the switch (completing the circuit)
Always check that connections are clean.
Switch off the current when not making a measurement.
When measuring resistance use low currents/voltages to avoid heating and changing the resistance you are measuring.
