Physics RP

Question 1

Specific heat capacity required. Practical.

Answer 1

Measure mass of water using balance.
Measure initial temperature of water using a thermometer.
Pour water into the kettle.
Put temperature probe in the water.
Switch kettle on.
Record temperature.
Measure the time using stop clock.
In five second intervals.
E=mc0

Question 2

Insulation.

Answer 2

Wrap N layers of newspaper around the metal can.
Heat water in a kettle.
Pour water in the metal can.
Use a measuring cylinder to measure volume of water.
Measure initial and final temperature with digital thermometer.
Use stop clock to measure 5 minutes.
Calculate temperature decrease.
Repeat with different layers of newspaper and 0 layers.
Use same initial temperature of hot water and the volume of water each time.

Question 3

Resistance of a wire

Answer 3

Measure length
Vary length.
Measure the current using amateur.
Measure potential difference using voltmeter.
Calculate resistance for each length.
V=IR
Plot Graph of resistance against length.
hazard: High current wire can overheat, burn the skin. Use low current.

Question 4

Current in a resistor at constant temperature varies with potential difference across the resistor for negative and positive current. RP

Answer 4

Measure the current or resistor using a meter.
Measure potential difference across resistor using voltmeter.
Very resistant or variable resistor.
Record range of values of current and potential difference.
Ensure current is low to avoid temperature increase which will give unfair values.
Switch circuit off between readings.
Reverse connection over resistor or of the power supply.
Of potential difference on current for negative current.
Plow a growth of current against potential difference.

Question 5

irregularly shaped object density required practical

Answer 5

Measure mass using a balance.
Fill Eureka can with water, water level with spout.
Place rock in water.
Collect water displaced with the measuring cylinder.
Water displaced is equal to the volume of the rocket.
P=m/V

Question 6

To investigate the radioactive source.

Answer 6

Sector very close to source.
Record the count rate.
Between the source and the detector.
Record new count rate.
Alpha will not penetrate through paper.
If count rate decreases then it is out for radiation.
Remove the paper and position aluminum between the source and the detector.
Record New count rate
Beta radiation would not penetrate through aluminium.
If count rate has reduced then beta is present.
If radiation penetrates through aluminium, then gamma is present.
Repeat investigation.
And calculate mean because radioactivity is a random process.

Question 7

Explain how the readings on both meters change when the environment conditions change.(series circuit) (6)

Answer 7

Resistance of LDR decreases as light increases.
Potential difference of total resistance unchanged.
Current increases.
Potential difference across fixed resistor increases.
p.d Across LDR decreases.
Reading on a voltmeter across the LDR decreases.
Potential difference shared between components and series.
The lower the resistance of LDR, the smaller the potential difference.
Reading on voltmeter decreases.