Monday, February 20, 2012

7.8

7.8

7.8
12 January 2012
10:24
·         
7.8 understand that ionising radiations can be detected using a photographic film or a Geiger-Muller detector
<<detection of radiation.pptx>>

detection of radiation.pptx Download this file

7.4 to 7.9 plenaries

7.4 to 7.9 plenaries

7.4 to 7.9 plenaries
01 February 2012
13:09
<<alpha, beta, gamma summary table.pptx>>

<<a,b,g and ionisation plenary questions.pptx>>

alpha, beta, gamma summary table.pptx Download this file

a,b,g and ionisation plenary questions.pptx Download this file

7.9

 7.9

7.9
12 January 2012
10:24
·         
7.9 recall the sources of background radiation
<<background radiation.pptx>>

Whys Guy

·         

background radiation.pptx Download this file

7.4 and 7.5

 7.4 and 7.5

7.4 and 7.5 starter
01 February 2012
10:00

Tell the person next to you…

·         What are the 7 parts of the electromagnetic spectrum you learnt in P3, Waves?
·         What are they in order of increasing frequency?

 

 

<<e-m spec.swf>>

(Note that microwaves are missing from this animation!)

 

 

 

 

 

 

 

 

 

Answers

·   Radio waves
·   Microwaves
·   Infra Red
·   Visible
·   Ultra violet
·   X-Rays
·   Gamma Rays

7.4 and 7.5
12 January 2012
10:24
·         7.4 understand that alpha and beta particles and gamma rays are ionising radiations emitted from unstable nuclei in a random process
·         7.5 describe the nature of alpha and beta particles and gamma rays and recall that they may be distinguished in terms of penetrating power

Producing Alpha, Beta and Gamma radiation

·         

 

 

<<decays emitting a,b,g.swf>>
<<producing a,b,g.pptx>>

Penetrating Power

·         
·         

 

 

<<penetrating power.swf>>
<<DJFPh107pene3.swf>>

 

 

<<Interactive simulation - penetration of radiation.swf>>
<<DJFPh109gammy5.swf>>
Ionisation

 

 

<<Animation - ionisation of atom by radiation.swf>>
<<DJFPh109ioniz2.swf>>
<<ionisation.pptx>>
Effect of magnetic and electric fields
<<effect of magnetic field on a,b,g.swf>>
<<effect of electric field on a,b,g.swf>>

producing a,b,g.pptx Download this file

penetrating power.swf Download this file

ionisation.pptx Download this file

Interactive simulation - penetration of radiation.swf Download this file

effect of magnetic field on a,b,g.swf Download this file

effect of electric field on a,b,g.swf Download this file

e-m spec.swf Download this file

DJFPh109ioniz2.swf Download this file

DJFPh109gammy5.swf Download this file

DJFPh107pene3.swf Download this file

decays emitting a,b,g.swf Download this file

Animation - ionisation of atom by radiation.swf Download this file

7.2

 7.2

7.2 starter
31 January 2012
11:35

Tell the person next to you…

·         The names of 3 subatomic particles
·         What properties do they have?
<<atomic structure - electrons orbiting the nucleus.swf>>
<<sub-atomic particles - drag and drop.swf>>

7.2
11 January 2012
14:49
·         7.2 describe the structure of an atom in terms of protons, neutrons and electrons and use symbols such as 146C to describe particular nuclei
<<Proton number and mass number.ppt>>
<<atomic structure of Li - mass and proton numbers.swf>>

sub-atomic particles - drag and drop.swf Download this file

Proton number and mass number.ppt Download this file

atomic structure of Li - mass and proton numbers.swf Download this file

atomic structure - electrons orbiting the nucleus.swf Download this file

P7 student objectives sheet

: P7 student objectives sheet

P7 IGCSE Physics Student Objectives.doc Download this file

6.8 to 6.10

6.8 and 6.9 starter
09 December 2011
08:51

Tell the person next to you…

·         What's an electromagnet? 
·         How is it different from a magnet?
<<Electromagnet lifting a car.swf>>

6.8 Field around current carrying conductor simulation
28 November 2011
15:06
Website:

Embed code for your blog:
<iframe src="http://www.walter-fendt.de/ph14e/mfbar.htm" style="border:0px #FFFFFF none;" name="myiFrame" scrolling="yes" frameborder="1" marginheight="0px" marginwidth="0px" height="800px" width="800px"></iframe>

6.8 and 6.9
01 December 2011
18:04
·         6.8 recall that an electric current in a conductor produces a magnetic field round it
·         6.9 describe the construction of electromagnets

 

 

<<Electromagnets.ppt>>
<<magnetic field around wire and a solenoid.swf>>

6.8 and 6.9 extension - bell
01 December 2011
18:04

 

 

<<electric bell animation.SWF>>

 

 

6.8 and 6.9 Plenary Multichoice questions
01 December 2011
18:13
<<6c Plenary Multichoice questions.pptx>>

6.10
01 December 2011
18:04
·         6.10 sketch and recognise magnetic field patterns for a straight wire, a flat circular coil and a solenoid when each is carrying a current
Straight wire = Right hand grip rule

Image001

Flat circular coil

Image002

Solenoid

Image003

6.8 to 6.10 Plenary questions

Image004

Image005

magnetic field around wire and a solenoid.swf Download this file

Electromagnets.ppt Download this file

Electromagnet lifting a car.swf Download this file

electric bell animation.SWF Download this file

6c Plenary Multichoice questions.pptx Download this file

6.7

6.7 starter
01 December 2011
19:37

Tell the person next to you…

1.              If the field lines are close together, what does this tell you about the field?
2.              If the field lines are widely spaced, what does this tell you about the field?
3.              If the magnetic field lines are parallel to each other, what does this tell you about the field?

Answers

1.              The field is strong
2.              The field is weak
3.              The field is of a constant strength - a "uniform" field

 

6.7
28 November 2011
15:08
·         6.7 know how to use two permanent magnets to produce a uniform magnetic field pattern

 

 

 

 

·  When the field lines are parallel, the field will be uniform

6.4

6.4
28 November 2011
15:07
•        6.4 understand the term ‘magnetic field line’

Observing the magnetic field around a bar magnet and a wire

magnetic field around a bar magnet and wire

·         
Use iron filings to observe the magnetic field around a bar magnet
·         Use plotting compasses to observe the field
·         Use the 3D field demonstrator to observe field

 

6.4 Field around bar magnet simulation
28 November 2011
15:06
Website:

Embed code for your blog:
<iframe src="http://www.walter-fendt.de/ph14e/mfbar.htm" style="border:0px #FFFFFF none;" name="myiFrame" scrolling="yes" frameborder="1" marginheight="0px" marginwidth="0px" height="800px" width="800px"></iframe>

Example:

6.4 plenary questions and Earth's Magnetic Field
01 December 2011
19:12
<<Plenary questions and the Earth's Magnetic field.ppt>>

Plenary questions and the Earth's Magnetic field.ppt Download this file

6.11

6.11
01 December 2011
18:04
·         
6.11 appreciate that there is a force on a charged particle when it moves in a magnetic field as long as its motion is not parallel to the field
Solar wind creating aurora animation

Timelapse of aurora
 

6.13

6.13 starter
12 December 2011
16:07

Practical - the current balance

·         Use a current balance to investigate what happens when a current flows in a magnetic field
·         How many magnetic fields are created by this apparatus?
·         How could you make the wire move further? (2 ways)
·         How could you change the direction the wire moves in? (2 ways)
<<Magnetic fields interacting - Force on current carrying wire.swf>>

Answers

1.              2 magnetic fields:
a.                  the uniform magnetic field created between the poles of the permanent magnet
b.                  the magnetic field around the wire when the current flows
2.               
a.                  Increase the current in the wire
b.                  Increase the strength of the magnetic field
3.               
a.                  Reverse the poles of the magnets
b.                  Reverse the direction of the current

6.13
01 December 2011
18:05
·         6.13 use the left hand rule to predict the direction of the resulting force when a wire carries a current perpendicular to a magnetic field

Image001

<<FLHR practice.pptm>>

6.13 FLHR simulation
28 November 2011
15:06
Website:

Embed code for your blog:
<iframe src="http://www.walter-fendt.de/ph14e/mfbar.htm" style="border:0px #FFFFFF none;" name="myiFrame" scrolling="yes" frameborder="1" marginheight="0px" marginwidth="0px" height="800px" width="800px"></iframe>

Example:

6.13 Plenary
12 December 2011
11:55
<<FLHR Animation - Force on current carrying wire.swf>>

Magnetic fields interacting - Force on current carrying wire.swf Download this file

FLHR practice.pptm Download this file

FLHR Animation - Force on current carrying wire.swf Download this file

6.6

6.6
28 November 2011
15:07
·         
6.6 sketch and recognise the magnetic field pattern for a permanent bar magnet and that between two bar magnets
Image001

6.18

6.18

01 December 2011

18:08
· 6.18 explain the use of step-up and step-down transformers in the large-scale generation and transmission of electrical energy
· http://youtu.be/LZKhGGBcYFI
>


6.18 answers

01 December 2011

18:08
[cid:image001.jpg@01CCE4AC.9D422F50]
[cid:image002.png@01CCE4AC.9D422F50]
[cid:image003.png@01CCE4AC.9D422F50]

National grid worksheet.doc Download this file

6.20

6.20

01 December 2011

18:08
· 6.20 recall and use the relationship (for 100% efficiency):

input power = output power

Vp Ip = Vs Is
>

6.19 and 6.20 Plenary answers

01 December 2011

18:08
[cid:image001.png@01CCE4AC.921B9210]
a. Vs/Vp=ns/np

Vs/2=80/20

Vs=8V


b. Vs/Vp=ns/np

Vs/10=20/100

Vs=2V


c. Vs/Vp=ns/np

Vs/240=20/400

Vs=12V


d. Vs/Vp=Ns/Np

Vs/4=2000/50

Vs=160V

[cid:image002.jpg@01CCE4AC.921B9210]
2. Vs/Vp=ns/np

3/24=ns/480

ns=60turns

[cid:image003.jpg@01CCE4AC.921B9210]
a. Iron (Why? Iron is a magnetically soft material - it can be magnetised and lose its magnetism easily. This is necessary in a transformer as the magnetic field needs to change repeatedly)
b. electrical energy in the primary coil => magnetic energy in the core =>electrical energy in the secondary coil
c. dc current produces a steady magnetic field in the core. To induce a current in the secondary coils there must be a changing magnetic field in the core.

[cid:image004.jpg@01CCE4AC.921B9210]
a. Step down (because the voltage decreases)


b. Vs/Vp=ns/np

12/240=ns/1000

ns=50turns


c. P = V x I

24 = 12 x I

I = 2A


d. Power in secondary = 24W


e. Power in primary = 24W


f. P = V x I

24 = 240 x I

I = 0.1A


g. The current would be greater/double

Why?

Efficiency = Useful Pout/Total Pinx100

50 = 24/Total Pin x 100

Total Pin = 48W

P = V x I

48 = 240 x I

I = 0.2A

transformer animation with sliders and example calculations.swf Download this file