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A2 Physics Unit 4 Jan 2010 Multichoice KS5 A2 PHYSICS 2450 Mr D Powell

A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

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Page 1: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

A2 Physics Unit 4Jan 2010 Multichoice

KS5 A2 PHYSICS 2450Mr D Powell

Page 2: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Raw Marks....

A =B =C = D = E = U =

Page 3: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

C

Ft=mv-mu

Page 4: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B

v = 2x10-4 m3s-1 / 7.2x10-4m2 = 0.2778ms-1

mass per second = 1000kgm-3 x 2x10-4 m3s-1 = 0.2kgs-1

mv = 5.6 x 10-2

Page 5: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

Inelastic means that you lose some KE to thermal/sound in the smash

But you always conserve mass and total energy and momentum in any collision

Page 6: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A

=v/r = (6400 x103 x 2/ 24 x 602)/ (6400 x 103)

D

FBI for C

Page 7: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B........

Page 8: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B

Reason out what is happening to M on spring about a point. Time for cycle is down, up past zero to top and down to zero. i.e. 0.5s x 4 = 2s A is only halfway down

Page 9: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A Why?

B – it is in phaseC – It is the reverse!D – can happen in chemical or electrical systems as well

Page 10: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A

Changes cancel out

1

4

4

)2(

22

22

'

'

221'

221'

F

F

r

mmF

r

mmGF

Page 11: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

Look at idea of velocity in circle v=r

Force on moving object in circle is F=mv2/r

GM

RT

TR

GMF

fR

GMF

R

fmR

R

GMmF

rv

rv

32

2

2

3

223

22

2

222

2

4

4

)2(

Page 12: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B

1. Use formula for gravitation field on Earth.

2. Plug in new case then divide 2 by 1 to cancel all terms and give x2y

G

rgM

gr

GM

EEE

2

2

G

rxygM

gr

GM

gr

GM

EEP

p

P

P

22

2

2

1

2

yxM

MGrgGrxyg

M

M

G

rgM

G

rxygM

E

P

EE

EE

E

P

EEE

EEP

2

2

22

2

22

Page 13: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

Think of formula...

The gravitational potential (V) is the potential energy (U) per unit mass:U = mV where m is the mass of the object. The potential energy is the negative of the work done by the gravitational field moving the body to its given position in space from infinity

Page 14: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A

Think of new situation and plug in numbers4

1

)2(

5.02

4

'

221'

20

21

F

r

QQF

r

QQF

Page 15: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

C 1. Work is only done then moving towards or away from electrode.

2. Equipotential means no PD between points

3. Hence no work against the field

Page 16: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B

E-field is uniformD = ½ then V = ½ to cancel

d

VqF

qEFd

VE

Page 17: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

C

E=V/d

Field is 1NC-1

Electric Potential is 1JC-1

V

d

Page 18: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

C1. Energy = ½ mv2 this is converted to potential energy V at point

P

2. There is no way that total energy can be zero at this point or it would simply sit there and not reverse direction!

Page 19: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

........

Page 20: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

B

CV=QQ=ItCV=ItCV/I =t

Page 21: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

Look at equations Q = CV & E = ½CV2 Q V , E C

Now put in values ratios are 1000: 100 in formula

Both come out as 10:1 X:Y

Page 22: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

D

F=BILF = 0.2T x 8A x 0.4mF = 0.64N

Electrons = 8 x 1028 electrons/m3 x (1x10-6m2 x 8 x 0.4m)

Force per electrons = 2 x 10-23N

Page 23: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

C

Same plane so no effect

Br = mv / Bq

r m only correct one!

Page 24: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell
Page 25: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A

Using formulae for induced e.m.f

Rearrange to second line....(mine complex version!)

BAN

t

tBAN

sin

sin

Page 26: A2 Physics Unit 4 Jan 2010 Multichoice A2 Physics Unit 4 Jan 2010 Multichoice Mr D Powell

Mr Powell 2008Index

A

1. Conducting Rod of length l moves through magnetic flux density (field strength per unit area) B at constant speed v....

2. Distance travelled by rod is v∆t

3. Area of flux it cuts is lv∆t.

4. Magnetic flux = = BA = B x lv∆t

5. Faraday law states e.m.f = ∆/ ∆t = Blv∆t/ ∆t = Blv6. e.m.f = 1x10-5T x 60m x 150ms-1 = 0.09Tm2s-1

= 0.09 Vsm-2m2s-1

= 0.09V