Practical Skills

Question 1

When adding or subtracting data, how do you work out the uncertainty in the sum?

Answer 1

Add the absolute uncertainties in the things you are adding or subtracting

Question 2

When multiplying or dividing data, how do you work out the uncertainty in the product?

Answer 2

Add the percentage uncertainties In the things you are multiplying or dividing

Question 3

When raising something to a power, how do you work out the uncertainty in the product?

Answer 3

Multiply the percentage uncertainty by the power

Question 4

How would you work the uncertainty in the gradient of a graph?

Answer 4

Difference between the highest possible and lowest possible gradient divided by 2

Question 5

How would you work the uncertainty in the y intercept of a graph?

Answer 5

Difference between the highest possible and lowest possible y intercepts divided by 2

Question 6

How could you reduce the percentage uncertainty in a distance measurement on an oscilloscope trace?

Answer 6

Reduce the time base setting to a lower time per division, measuring a larger distance reduces percentage uncertainty

Question 7

Explain how to show that x decreases exponentially with n

Answer 7

Draw a graph of lnx against n, will produces a linear graph with a negative gradient