Statistics

Order Description

Experimental data
Primary data
You will perform a short experiment where you are going to record the time taken for 10 oscillations of a mass on a spring.
1. Arrange a clamp stand so that you hang a spring on it.
2. Place 250 g of mass on that spring
3. Pull the mass down from the bottom by about 5 cm a let go. 1 oscillation is when it bounces up and then falls back down to its starting position. Time how long it takes for the mass to oscillate ten times. Record the data and plot a bar chart of the times.
Secondary data
Boltzman – Maxwell data
Speeds [m/s] Number of molecules
0 – 399 4
400-799 6
800-1199 16
1200-1599 20
1600-1999 13
2000-2399 12
2400-2799 10
2800-3199 10
3200-3599 5
3600 -3999 3
4000-4400 1
Life expectancy data
Year’s frequency
0 – 4 0
5-9 0
10-14 1
15-19 1
20-24 1
25-29 1
30-34 1
35-39 2
40-44 2
45 -49 2
50-54 2
55-59 3
60-64 3
65-69 3
70-74 14
75-79 16
80-84 19
85-89 16
90-94 12
95-100 3

Standard deviation Task
For your three sets of data please calculated the standard deviation. You can use an online calculator, but you must take screen shots and include this in your evidence
Standard error task
For your three sets of data please calculate the standard error. Use the formula and show how you get your answer.
Confidence limits task
Calculate one confidence limit from each data set. Find the upper and lower limit for one value from each data set. Show your working.
Bar chart task
Draw a bar chart for each of your three sets of data
Skewness task
For each of your bar charts please identify the trend of the data and indicate whether or not skew is present. You may want to draw on your graph to demonstrate your trend more clearly
Probability task
1. In nuclear physics we can describe radioactive decay rates as a probability. A substance can be considered radioactive if there are 3.7 x 10 10 nuclei decaying per second. This tells us that the probability of a decay is ;
P[decay] = 1
3.7×1010
Imagine you had 1 mol of a substance which is 6.02 x 1023 atoms. Can you calculate the expected number of atoms that would decay in one second for a radioactive substance? Use the formula for expectation to show how you get your answer
2.
The following diagram shows some information about the ratios of possible eye colours of a child born form parents one of brown eyes and one of blue eyes.
B = brown, and is dominant, b = blue and is submissive

1/4 = BB – brown eyed
1/2 = Bb – brown eyed
1/4 = bb – blue eyed

If the family had 12 children can you work out the expected values for each possible genetic possibility for eye colour. Use the formula for expectation to show how you get your answer.