practices paper 2 Flashcards
(22 cards)
what is the setup for charles law
- Boiling water bath with capilary tube and thermometer fixed to a ruler
the method for charles law
- Poor boiling water in to a capilaray tube and thermometer, measure height every 10 degrees, repeat three times for averages, plot a graph of height against temp and extrapolate for absoloute zero
what is the setup for boyles law
Syringe fixed to a clamp stand with hanging masses
independent, dependent and control variables for Charles law
Independent : temperature
dependent : volume
control :P,n,N
method for Boyles law
- Hand masses from a syringe making sure to leave time before recording volume as temperature needs to be constant, record masses and volume in a table
- In order to find pressure measure the diameter of the syringe with a veneer caliper.
- subtract pressure from value of atmospheric pressure (101kp) and record on a table of pressure against volume
what can systematic errors be due to in Boyles law
- friction with syringe
Gay lussacs law method
- container of gas submerged in a water bath with a thermometer connected to a bourdon gauge
method for gay lusascs law
Poor boiling water in, measure the pressure of the bourdon gauge every 10 degrees, record value and plot graph
capacitor discharge to determine the capacitance setup
battery in in circuit with capacitor connected to a switch. Volt meter in parallel and resistor in series
capacitor determine method
Charge capacitor, use an analog voltmeter as this will be easier to read exact reading due to refresh rate of digital. To determine a resistance perform multiple discharges to find one where voltage decreases at an acceptable speed. Record voltages at differnt times and plot a table, Ln the voltages to determine capacitor with a graph
explain setup to measure the induced emf
- Battery in series with a coil. Use a variable resistor and AC ammeter to make sure current remains constant therefore the value of B remains constant
explain the method for induced emf
- fix a search coil in the center of a coil with a protractor underneath.
- attach an cathode ray oscilloscope across the search coil
- Turn time base off and make sure suitable voltage scale is used
- rotate the search coil through 90 degrees measuring max emf at each point
- plot graph of sin against the emf to test proportionality where the gradient is BANw
independent dependent and control variables in the search coil experiment
Independent - angle of search coil
dependent - Max EMF induced
control - area, current, number of turns
inverse square law setup
- Source placed a distance away from Geiger muller tube connected to a counter, use a meter rule to measure
Method for inverse square law
- account for background (three measurements when source is not there)
- record the number of counts per minute at different distances
- repeat three times for accuracy
- plot a graph of counts per second against 1/x^2 or 1/root c against x, gradient should be constant
what can the systematic error be due to in the inverse square law experiment
the distance that you measure between source and the tube not being correct
the tube being faulty
safety in inverse square law
warning signs
led lined
don’t point
handle with tongs
independent and dependent variables in the F=BIL experiment
independent - current, B, L
dependent - Force
controls in the F= BIL experiment
- use the same magnet therefore same B
- Fix wire in place therefore constant length of wire in the field and also flexing of the wire doesn’t cause a change in B as horseshow magnet do not produce uniform field
- use a thick wire to avoid flexion
method for F=BIL
- place magnet on balance and zero
- measure readiing on balance for differnt currents from 0.5 - 3
- plot graph of force against current and use gradient to calculate B
what is DC rippling
when smoothing out the current from AC to DC current is lumpy and can cuase errors in experiments
if absolute uncertainty is the same what should be done
pick the highest percentage uncertainty to be your uncertainty
