Practicals

Question 1

What is a advantage of moving a radiation detector closer to a gamma source?

Answer 1

• Reduced exposure time of experimentor to source
• Greater distance away so distance between source and experimentor is maximised

Question 2

What does Rc stand for?

Answer 2

Corrected count rate

Question 3

How do you calculate corrected count rate?

Answer 3

Total count rate - Background count rate = Corrected count rate

Question 4

What are the units for count rate?

Answer 4

1/s

Question 5

What is the equation for Δd when investigating the inverse square law for gamma radiation, stating what each non-constant means?

Answer 5

Δd = (10^a - 10^b)/n
- Where a and b are any plotted value of log(d/mm) with 2 or more d.p
- Where n = 1,2,3 or 4

Question 6

State the nature of radioactive decay for a radioactive source?

Answer 6

The source emits photons unpredictably

Question 7

What happens to intensity as the order of maximum increases?

Answer 7

• Maximum become wider
• Maximum intensity reduces

Question 8

What is the use of a mirror when reading an analogue meter?

Answer 8

• Move position until needle is aligned with reflection of needle in mirror
• This reduces parallax error

Question 9

Describe how to switch a capacitor from one voltmeter socket to another, while keeping the voltmeter in full scale

Answer 9

• Discharge the capacitor
• Change the output voltage to less or equal to the socket voltage
• Reconnect the capacitor
• Adjust voltage so meter is full scale

Question 10

How do you get an accurate result for the time constant?

Answer 10

Increase the time interval for concurrent half lives

Question 11

How do you use a result to check if a theory is correct?

Answer 11

By checking for any errors in the result

Question 12

For a table of values of voltage as a capacitor discharges over time, why might the values of voltage be to the nearest volt?

Answer 12

To the nearest volt due to scale resolution