Physics Unit 4 JUNE 11/6/12

[Evolution]

A thread to share physics unit 4 notes, and to get help

 

[Evolution]

Here are some notes:
http://getrevising.co.uk/resources/edexcel_physics_unit_4_topic_1_further_mechanics
http://getrevising.co.uk/resources/edexcel_unit_4_physics_revision_material_useful
http://6ph04.weebly.com/index.html
http://www.studentforums.biz/reference-material-83/everything-you-need-for-edexcel-a2-biology-13416/

 

[Evolution]

These extra notes, aren't written by me, they are written by a guy in some other forum.

​

Momentum and Force​

• Use the equation p=mv​

• Relate net force to rate of change of momentum in situations where the masses of the objects do not change (this is Newton's second law of Motion)​

​

Momentum and Collisions​

• Apply the principle of conservation of linear momentum to problems involving objects moving along in a straight line​

• Derive and use the expression Ek=p^2/2m for the kinetic energy of particles (for particles moving much more slowly than the speed of light)​

• Use data to calculate the momentum of particles​

• Apply the principle of the conservation of linear momentum to problems in one and two dimensions ​

o (so you need to be able to resolve forces, and speeds, using trigonometry)​

• Explain the principle of the conservation of energy​

o Energy cannot be created or destroyed. Energy can be transferred from one form to another but the total amount of energy in a closed system will not change.​

• Use the principle of the conservation of energy to determine whether a collision is elastic or inelastic​

o Work out the total kinetic energy before (Ek1) and after (Ek2) the collision. If Ek1=Ek2, the collision is elastic, as kinetic energy is conserved in elastic collisions. If Ek1>Ek2,the collision is not elastic, as energy has been transferred to forms other than kinetic.​

​

Circular Motion 1​

• Express angular displacement in radians and in degrees , and convert between those units​

• Explain the concept of angular velocity​

• Use the relationships ν=ωr and Τ=2π/ω​

• Derive and use the expressions for centripetal acceleration a= ν2/r and a=rω2​

​

Circular Motion 2​

• Explain that a resultant force (centripetal force) is required to produce and maintain circular motion.​

• Use the expression for centripetal force F=ma =mν2/r​

 

[Evolution]

It's seems like either no1 is taking phys this session, or it's just that nobody gives a shit about it lol

 

[the golden girl]

I'm repeating it but hmmm ,will start taking it seriously today inshAllah

 

[the golden girl]

Let's make a check list

I'm basing mine on the Specification and what I think is Important ... btw do we have to study AS ?

Topic-wise checklist ;

http://www.fizix.info/resources/gce08/unit4topic1_target_sheet.pdf
http://www.fizix.info/resources/gce08/unit4topic2_target_sheet.pdf
http://www.fizix.info/resources/gce08/unit4topic3_target_sheet.pdf

 

[Evolution]

Let's make a check list

I'm basing mine on the Specification and what I think is Important ... btw do we have to study AS ?

Topic-wise checklist ;

http://www.fizix.info/resources/gce08/unit4topic1_target_sheet.pdf
http://www.fizix.info/resources/gce08/unit4topic2_target_sheet.pdf
http://www.fizix.info/resources/gce08/unit4topic3_target_sheet.pdf

not really. no. But you need to know you A2 really well, how do you find yourself when solving past papers? I still have a lottt of mistakes

 

[the golden girl]

not really. no. But you need to know you A2 really well, how do you find yourself when solving past papers? I still have a lottt of mistakes

I haven't even looked at them yet *sigh*

I need to go for now, so salam

 

[Evolution]

yah, bbye and good luck, if you got any questions here's the place for them. I'll log in after a while to see if you need anything.

 

[the golden girl]

I\ll make sure I log everyday when I have the time to help ya out and ask for your help inshAllah , jazaki Allah khair

 

[svenas]

yah, bbye and good luck, if you got any questions here's the place for them. I'll log in after a while to see if you need anything.

hii... how r u and hows studying goin on? Its really so tough and 3 more days left actually i hve a que for capacitors: Describe how you would show experimentally that the pd across a 470 microF capacitor is proportional to the charge on the plates of the capacitor.

 

[Evolution]

OK

1. set up a circuit, with a variable resistor, a variable power supply, the capacitor, an ammeter, a coloumeter (measures charge), and a multimeter (measures voltage).
2. Close the circuit, and change the resistance of the variable resistor to make sure the current is constant.
3. You can make sure the current is constant by looking at the ammeter.
4. Keep reading the charge at equal time intervals, and collect your data in a table.
5. Do the same with the voltage.
6. Plot a graph of voltage against charge, the gradient should be constant, and the graph a straight line. This indicates that the charge and potential difference are proportional.

 

[svenas]

hmm which paper is that on? and give me a sec

no its nt frm a paper its frm my book

 

[svenas]

OK

1. set up a circuit, with a variable resistor, a variable power supply, the capacitor, an ammeter, a coloumeter (measures charge), and a multimeter (measures voltage).
2. Close the circuit, and change the resistance of the variable resistor to make sure the current is constant.
3. You can make sure the current is constant by looking at the ammeter.
4. Keep reading the charge at equal time intervals, and collect your data in a table.
5. Do the same with the voltage.
6. Plot a graph of voltage against charge, the gradient should be constant, and the graph a straight line. This indicates that the charge and potential difference are proportional.

Well.. why do we have to make the current constant ?

 

[svenas]

Well.. why do we have to make the current constant ?

Plz i need the answer urgent i already lost hope for 2morrow's exam i don kno whts gonna happen to me during the exam

 

[Evolution]

cause current changes the charge, therefore the expirement won't be fair. You have to control all the other variables and make sure that only the potential difference and charge are changing. Otherwise you will have error with your results.

 

[svenas]

cause current changes the charge, therefore the expirement won't be fair. You have to control all the other variables and make sure that only the potential difference and charge are changing. Otherwise you will have error with your results.

hmm bt if current is constant then how would the charge increase? im getting confused in ths question and btw how's ur preparation for 2mrow's exam i seriously find past papers hard

 

[Evolution]

same, it's really annoying, all we can do now is try and revise every book we see.

 

[svenas]

same, it's really annoying, all we can do now is try and revise every book we see.

why didn't u take unit 4 in jan?

 

[svenas]

why didn't u take unit 4 in jan?

Hii plz if u can solve 4 me this que . Thanks in advance
(ii) Calculate the theoretical energy released when a U nucleus is formed from individual protons and neutrons. Give your answer in MeV.

Data (masses):

U = 238.0003 u ,proton = 1.0073 u, neutron = 1.0087 u