Comparison of fields HW for Ms H - both groups

HW is to make a table comparing gravitational and electric fields in terms of the equations, units and situations and definitions of the following:

Force between two objects
Attractive or repulsive
Uniform field strength
Radial field strength
Potential
Work done
Potential gradient

13b - due for Friday's lesson 11th Nov
13d - due for next Tuesday's lesson 15th Nov

Answers to grav multi choice questions from before half term

This is for the questions starting with " A spacecraft of mass M.."

M1.C

[1]

M2.C

[1

M3.B

[1]

M4.C

[1]

M5.A

[1]

M6.A

[1]

M7.A

[1]

M8.C

[1]

M9.A

[1]

M10.B

[1]

13d Important notice - TEST for Ms H

Dear Y13
We have a test on Wednesday 2nd November, please use the holidays to revise and also complete the questions on Isaac Physics as revision
Thanks and happy half term!
Ms H

13b HW (continued from lesson) Ms H

•What is the potential gradient at a distance of a) 0.25m  b)1.00m

•Use your graph to work this out.

•What is this representing?  

13b HW from Monday 17th Oct Ms Hamnett

Answer the following questions in full using the idea of electric fields.
Bring this, your multiple choice HW and some revision evidence form unit 1 to the next lesson on Friday

1.  Why did the metal ball bob back and forth?

2.  Why does charge leap across the gap between the two coins?

3.  Why does water move from the tap?

4.  Why does your hair go static and get attracted to the rod?

5.  How does the gold leaf electroscope work?

Explain each phenomenon in terms of electric fields

Use the words charge, electron, field, positive, negative, attract, repel in your answer

Both Year 13 groups Pendulum homework

Make sure your graphs and question 1 from the experiment booklet are complete (or as complete as you can) by Thursday 6/10.

13b HW from Monday 3rd October

1.So why do astronauts feel weightless in orbit? 

Explain this in your own words, including the key words below

centripetal, gravity, free fall,  contact forces, velocity

2. What happens if you try to put an object into orbit;

•Too slowly

•Correct speed

•Too fast

•Draw a diagram to show this

3. Work out the speed of the ISS (orbit 400km, T = 92 minutes)

4. Do your other HW from previous blog post.

Circular motion test markscheme

https://drive.google.com/file/d/0B5q9mMSoKpAzYzJESXg2b0ZYcDA/view?usp=sharing

And yes, the first page is blank, I haven't messed up and posted the wrong file!

13b and 13d cover work Friday 30th September(13b) and Tuesday 4th October (13d)

Dear Y13
Apologies for missing a lesson for each group
Please join Isaac Physics as detailed on previous blog post, and complete the assignments there.
In addition, please finish and mark the questions given in class.
Copies are available here 
https://drive.google.com/drive/folders/0B_-6rEo3ljnVSXFCM21udnRXU00?usp=sharing
In addition research and make notes on geosynchronous and polar satellites, including the features and uses of each.
Enjoy!
Ms H

Circular motion homework

Answer the following Qs on lined paper.  They combine the circular motion and gravitational force topics.

1. Show that the centripetal force needed to make the Earth orbit the Sun and the gravitational force between the Earth and the Sun are the same size.  149.6x10^6 km seperation.
2. Show this is also true for Neptune.  Neptune’s mass is 1.02×10^26 kg and it is 4.498x10^9 km
3. If planet X existed at 1000 times the distance from the Sun that the Earth is and was 10 times the mass, what length would its year be?
4. How would this year change if it was 100 x the Earth’s mass?

Due Thursday 29th Sept.

Joining Isaac Physics by Thursday afternoon

Please join Ms Hamnett's group on Isaac Physics by - either click on the link below,

13b (who were taught by Ms Hamnett last year)
either click on the link below,
https://isaacphysics.org/account?authToken=YTU4NJ

or enter the code below on the teacher connections tab

YTU4NJ

13d  (who were not taught by Ms Hamnett last year)
either click on the link below,
https://isaacphysics.org/account?authToken=NMVLMD

or enter the code below on the teacher connections tab
NMVLMD


Thanks

Ms H

Isaac Physics homework

Accessing Isaac Physics for Dr Hardwick's homework

Go to the website here https://isaacphysics.org/ make an account and join the correct group below:

13D click here https://isaacphysics.org/account?authToken=QRWQ3YJ or use this code QRWQ3YJ

13B use click here https://isaacphysics.org/account?authToken=NZE2ZD or use this code NZE2ZD

You should then find the homework in menu --> my assignments

Come and see me if you have any difficulties accessing the tasks.

Space problem and other HW

•If you were floating in space infinitely far from any other object, how could you save yourself?

Please also bring your answers to the NULOG questions given in class last week.  

13b - you also have gravitation exam questions, a graph to finish and working out the gradient between r2 and r3 as well as what this represents, due to missing a lesson on Friday for the INSET day.

Help with revision - here is where and when to find us

Timetable for A level support

Day	Date	Time	Person	Room
Mon	6th June	10.50	CHA	Portacabin office/ R22
Tue	7th June	9.30	CCA	R1
Wed	8th June	email
Thu	9th June	email
Fri	10th June	INSET

Day	Date	Time	Person	Room
Mon	13th June	11.50	CCA	R1
Tue	14th June	8.30	CHA	R block office?
Wed	15th June	email
Thu	16th June	2.30	CCA	R1
Fri	17th June	9.30 – 11.30	CHA	R block office ?

Day	Date	Time	Person	Room
Mon	20th June	10.50	CHA	R block office ?
Tue	21st  June	9.30	CCA	R1
Wed	22nd  June	email
Thu	23rd  June	email
Fri	24th June	10.50	CHA	R block office

Monday 27^th June as Monday 13^th June

If you can’t find us, try in the science office.  Often best to email first

cca@cheney.oxon.sch.uk or cha@cheney.oxon.sch.uk

Thanks and happy revising!

Claire

EMPA practice answers

A2 EMPA practice questions and sample results

Section 2

l /m	h /m	h /m	h /m	Mean h /m
0.860	0.370	0.365	0.375
0.801	0.503	0.504	0.492
0.724	0.668	0.673	0.672
0.651	0.809	0.812	0.808
0.553	0.945	0.946	0.949

https://www.researchgate.net/publication/252262271_Period_of_an_Interrupted_Pendulum

https://www.youtube.com/watch?v=MEgPkkQSt7s

1. For the largest  value of l what is the range of h ? 0.010m
2. For the largest  value of l what is the percentage uncertainty of h ?1.35%
3. For the smallest value of l what is the uncertainty of h ? 0.002mm
4. For the smallest value of l what is the percentage uncertainty of h ? 0.21 approx
5. Draw a graph of your results on the grid provided.
6. What is the pattern shown by these results, and how accurate are they? How do you know?line goes through the points, ranges are small, points close to line of best fit
7. What are the main sources of uncertainty in this experiment? measuring height with ruler as bob is round, 
8. What equations describe the energy changes involved in this experiment? mgh to 1/2mv squared
9. A pendulum swings from a support post and another post is added to interrupt its swing. We desire to know the maximum height at which the pendulum will perform a full loop around the post. The pendulum requires both potential and kinetic energy in order to complete a full loop. Therefore, it will never be able to return to its height of release while completing a full loop. Ultimately, the pendulum has enough energy to complete a full loop when interrupted at a height equal to two-fifths its initial height of release.
10. How could you use your data to verify the above statement? calculate gradient and compare to that value - should equal 0.4 I think, but probably won't!
11. A student performs a similar experiment but instead measures the maximum height the pendulum reaches once it hits the rod and swings around it.  What would you expect the student to find?height it reaches = height it is released from - directly proportional
12. Which of your measured values could you use to verify this relationship? Need hight it reaches, or you could work that out by subtracting h from total length of pendulum and use the l as well.
13. Describe the motion of the pendulum on each side of the rod. SHM and then circular motion
14. What is the gradient of the graph of the above results?0.4 maybe, or 0.6. 

For those resitting AS EMPA

Here are some practice questions, to complete, we will go through these on Tuesday 2pm in the library (come at 2.30 if you have a period 5 lesson) ready for the exam the next day in the morning 830 am.
Ms H

AS EMPA practice questions

Results from Task 2

V1 /V	V2 /V	V3 /V	V3 /V	V3 /V	V3  /V average
4.03	2.00	3.73	3.71	3.72	3.73
3.50	1.76	3.28	3.26	3.30	3.28
3.01	1.52	2.82	2.82	2.82	2.82
2.50	1.26	2.36	2.35	2.35	2.35
1.99	1.32	1.87	1.87	1.87	1.87
1.50	1.00	1.42	1.42	1.42	1.42
1.00	0.66	0.94	0.94	0.94	0.94

Questions

1. For the largest  value of V₁ what is the range of V₃ ?
2. For the largest  value of V₁ what is the percentage uncertainty of V₃ ?
3. For the smallest value of V₁ what is the percentage uncertainty of V₃ ?
4. For the smallest value of V₁ what is the uncertainty of V₁ ?
5. For the smallest value of V₁ what is the percentage uncertainty of V₁ ?
6. Draw a graph of your results on the grid provided
7. Does your line of best fit go through the origin?  Why/ Why not?
8. Were your results accurate?  Why/ why not?
9. What do you think was in the concealed unit?  Why?
10. Draw the circuit for each part of the experiment you did – what were you connecting?
11. How does potential difference split between components in series? In parallel?
12. If given the value of two of the resistors in the network, how could you use your graph to find the third?
13. What is the gradient of the graph of the above results?
14. What does this gradient represent?
15. If R2 = 1 kilo ohm, what is R3?  Use your graph to work this out.

For the above calculation, what is the percentage uncertainty for R3?  Show your working

Turning points questions to do for HW for next Friday

1.Give one reason why Huygens’ wave theory of light did not replace Newton’s theory of light when the fringe pattern due to double slits was first observed. (1)

2.The interference fringe pattern observed by M’n’M on their interferometer did not shift when the apparatus was rotated by 90°. Explain the significance of this null observation. (1)

3.   Discuss the significance of Einstein’s explanation of the photoelectric effect. (2)

4.   Millikan found that the charge on an oil droplet was always in multiples of e. Explain the significance of this result. (1)

5.   What was the significance of Thompson’s calculations of the specific charge of an electron? (2)

In case you lose it - and here are the links for EMPA

A2 EMPA practice questions and sample results

Section 2

l /m	h /m	h /m	h /m	Mean h /m
0.860	0.370	0.365	0.375
0.801	0.503	0.504	0.492
0.724	0.668	0.673	0.672
0.651	0.809	0.812	0.808
0.553	0.945	0.946	0.949

https://www.researchgate.net/publication/252262271_Period_of_an_Interrupted_Pendulum

https://www.youtube.com/watch?v=MEgPkkQSt7s

1. Calculate the means and add to the table.
2. For the largest  value of l what is the range of h ?
3. For the largest  value of l what is the percentage uncertainty of h ?
4. For the smallest value of l what is the uncertainty of h ?
5. For the smallest value of l what is the percentage uncertainty of h ?
6. Draw a graph of your results on the grid provided.
7. What is the pattern shown by these results, and how accurate are they? How do you know?
8. What are the main sources of uncertainty in this experiment? 
9. What equations describe the energy changes involved in this experiment?
10. A pendulum swings from a support post and another post is added to interrupt its swing. We desire to know the maximum height at which the pendulum will perform a full loop around the post. The pendulum requires both potential and kinetic energy in order to complete a full loop. Therefore, it will never be able to return to its height of release while completing a full loop. Ultimately, the pendulum has enough energy to complete a full loop when interrupted at a height equal to two-fifths its initial height of release.
11. How could you use your data to verify the above statement?
12. A student performs a similar experiment but instead measures the maximum height the pendulum reaches once it hits the rod and swings around it.  What would you expect the student to find?
13. Which of your measured values could you use to verify this relationship?
14. Describe the motion of the pendulum on each side of the rod.
15. What is the gradient of the graph of the above results?
16. What does this gradient represent?