required practicals

Question 1

Describe a practical for finding a material’s specific heat capacity.

Answer 1

specific heat capacity:
1) if solid, two holes for thermometer and heater
if liquid, place in beaker
2) measure mass of solid or liquid
3) record initial temperature
4) wrap insulating layer around beaker or solid to reduce energy transferred to surroundings
5) connect to joule-meter and power pack to immersion heater
6) set to 10V, turn on and start stopwatch
7) leave for 30 minutes
8) record joules and final temperature
9) place into equation (on sheet)

Question 2

Describe a practical to investigate the effectiveness of thermal insulators.

Answer 2

investigating energy transfers:

1) boil water, pour into seal-able beaker
2) measure temperature
3) seal for 5 minutes
4) remove lid and measure temperature
5) pour water away and allow beaker to cool
6) repeat with beaker wrapped in different materials
- the lower the temperature change, the better the insulator

Question 3

Describe a practical to investigate the factors affecting resistance.

Answer 3

factors affecting resistance:

1) attach a wire to a metre rule
2) set up circuit with a switch, battery, ammeter and voltmeter connected in parallel to the metre rule
3) attach a crocodile clip at 0 cm on rule and second somewhere else and record length
4) close switch, record A and V
5) open switch, move second crocodile clip… repeat
6) calculate resistance for each length (V/A)
- the longer the wire, the greater the resistance

Question 4

Describe a practical to investigate the I-V characteristics of circuit components.

Answer 4

I-V characteristics:

1) set up circuit with battery, ammeter, variable resistor and voltmeter across component
2) read V and A across component
3) repeat after adjusting variable resistor
4) switch direction of battery and repeat
5) plot I-V graph
6) switch component and repeat

Question 5

Describe a practical to find the density of a regular solid.

Answer 5

density of regular solid:

1) measure each side with ruler and calculate volume
2) place on balance to measure mass
3) place into equation

Question 6

Describe a practical to find the density of an irregular solid.

Answer 6

density of irregular solid:

1) place on balance to measure mass
2) fill Eureka can with water
3) place measuring cylinder by spout
4) place object in can
5) read volume on cylinder (displaced water)
6) place into equation

Question 7

Describe a practical to find the density of a liquid.

Answer 7

density of liquid:

1) measure volume in measuring cylinder
2) place cylinder on balance at 0
3) fill with liquid and record mass
4) place into equation