PRACTICALS Flashcards
Experiment for finding the value of g
EQUIP: meter rule, heavy steel ball, light gate to calculate time
EXPERMIENT: Drop ball from height s, record the time it takes as t.
RECORD: Use s = ut + half at squared,
plot h against t^2, gradient = s/t^2. a = 2s/t^2.
Gradient is double g, so g = gradient / 2
Repeat results and find average value
SAFETY: heavy ball so stand back
How to determine Young’s modulus experiment (for wire)
EQUIP: table, long wire of material, safety goggles, ruler
Setup wire on tabletop with g clamp at the end so it stays. Put tape marker at start of scale.
Hang over edge of tabletop smooth pulley masses
Load masses and record the forces. Record extension as it goes.
E=stress/strain. Strain can be calculated with extension / original length
Stress is f/a, f is mg of the masses, and a is the pid/4 use a vernier calliper
PLOT force against extension. Gradient = e/mg, so young mod = L/(Agradient)
Experiment to measure resistivity of a wire
Setup circuit : 6v emf, with ammeter and voltmeter. Put a length of the wire across voltmeter
SAFETY: wire gets hot, careful or gloves
Increase the length of wire which the clamps are on and record L, I and V (raw). Record R too (V/I), (treated)
p = RA/L.
Plot R against L. A is constant, so calculate p with gradient
Experiment to investigate combinations of resistors
Put resistors over a fixed emf in different combinations such as
all in series, all in parallel, two in series and one in parallel. Calculate resistance with workings, then compare to actual resistance using voltmeter and ammeter to calculate R.
Experiment to investigate springs in parallel and series
SERIES
Measure original length, load the spring with weight, keep adding and recording extension const mass
Plot extension against number of springs
PARALLEL
Set two springs up with a 1kg rod hanging off them. Record extension and original length.
Add more springs and plot extension against number of springs
