AS Physics P1 MCQs Preparation Thread.

[kinglynx]

honestly get your stuff togther and post the right paper

10
momentum before = momentum after
so mv + m*0 = mv
total momentum = mv = 2mv'
v'=v/2

KE = 0.5mv^2 so 0.5 * 2m * (0.5v)^2 =0.25mv^2 so answer is A

11
resultant torque is non zero as you have 2 3oN forces
rersultant force is non zero as 2 20N forces are pulling it

21
answer is B because after T the material undergoes plastic deformation
24
at constant temp speed of air is constant so F is inversely proportional to wavelength

26 and 27
[no idea]

31
answer is A you need to learn definition of EMF

33
power is I^2R so proportional
and when you have 2 resistors in parallel the total resistance is less than individual resistance of each one so a higher resistance means more power across it and less across other components

36
voltage across R1 is X and R2 is L-x so answer is D

thank you, it was ONE MISTAKE, jesus, look at my other posts i post all the questions in beautiful screenshots...

 

[Oliveme]

Asalam-o-Alaikum. Please help me with these questions -------> 9, 13, 14, 27 and 29.
for 27, why don't we multiply charge (1.6 x 10^-19) by 2 as there are two protons.

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w09_qp_11.pdf
http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w09_ms_11.pdf
Thank you very much. May Allah bless you.

 

[fatemakhan]

Any one pls help me out wit dese questions plsss
Q 13 25 26 of N09
Q8 15 20 of J10 variant 12
q5 N10 variant 11

HELP WILL BE APPRECIATED THANKS ALOT

Q5 of N10 variant 11:
60 sec(1 min) = 3000 revolutions
1 sec = 50 revolutions
therefore,50 is the frequency
time period=1/50=0.02 sec.
convert into millisec = 20 ms
now B seems to be the most clear scale for this...

 

[fatemakhan]

Any one pls help me out wit dese questions plsss
Q 13 25 26 of N09
Q8 15 20 of J10 variant 12
q5 N10 variant 11

HELP WILL BE APPRECIATED THANKS ALOT

Q8 of J10 variant 12;
h must be decreasing,right??so it must b from A or B
the ball falls under gravity(NO AIR RESISTANCE) , there will be constant acceleration and the speed will increase....so the gradient of the s-t graph must get increasingly steeper(difficult to walk on,if u ever try walking on a graph,lol)
20 of J10 variant 12
Q20: for a rubber band..the force is proportional to the extensoin but at the elastic limit, a large force is needed to for a small increase in the extension so it is A (answered by a-elwy)

 

[lavanyamane]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_s11_qp_13.pdf
Could someone please help me with Qs. 14, 15 and 33?

 

[Sana101]

hay can any1 help me with this pretty plz i kinda suck @ physics

A motorist travelling at 10ms–1 can bring his car to rest in a braking distance of 10m. In what distance could he bring the car to rest from a speed of 30 m s–1 using the same braking force?
A 17m B 30m C 52m D 90m

the marking scheme ans is D
so any 1 goody good out there mynd helping me out plzzzzzzzzzzzzzz

a) First off, bear in mind that since the 'same braking force' is used the acceleration is remaining constant. therefore first find the acc.
v^2 = 2as
10^2 = 2 x a x 10
a = 100/20=5
Now find the 's'
30^2 = 2 x 5 x 's'
s = 900/10 = 90 m

 

[Saloon]

hey guys, I'm also having a little bit of trouble in the M/J p13 2011 paper (attached) with questions numbers:
4- pls explain this uncertainty stuff thoroughly as i don't get when to add, subtract, multiply etc. and if anyone has any notes on this pls upload them
12
27
33- I don't get this I understand that p=I^2R... what I did was just use a resistance of say 2 ohm's, in parallel the resistance would then be 1 ohm (of the parallel combination w and x) if w is removed then the resistance of x will be 2 ohm's correct? Is this the reason why the power to x increases? and the power to Y and Z decrease because there is now more resistance ?

and for question 26 i saw that someone asked for the answer but nobody could answer it i have attached my answer (think it is right not sure though) correct me if its wrong. thanks for the help

 

[fatemakhan]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_13.pdf
Could someone please help me with Qs. 14, 15 and 33?

Qs. 14;
initial kinetic=2*final kinetic (how?? see the key sentence "rebounds vertically to half of its original height")
1/2 m*u^2=2*1/2*m*v^2
1/2=v^2/u^2
take square root both sides n C is the ans.=)

 

[bloody_mary]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_13.pdf
Could someone please help me with Qs. 14, 15 and 33?

14 i can't do

15 use the formula PE = KE + WD
so 2*9.81*3 = 0.5*2*v^2 * 5*7
58.86 = v^2 + 35

V^2 = 23.86
v= 4.88 which is 4.9 so answer is A

33 i just answered above

 

[omg]

hey guys, I'm also having a little bit of trouble in the M/J p13 2011 paper (attached) with questions numbers:
4- pls explain this uncertainty stuff thoroughly as i don't get when to add, subtract, multiply etc. and if anyone has any notes on this pls upload them
12
27
33- I don't get this I understand that p=I^2R... what I did was just use a resistance of say 2 ohm's, in parallel the resistance would then be 1 ohm (of the parallel combination w and x) if w is removed then the resistance of x will be 2 ohm's correct? Is this the reason why the power to x increases? and the power to Y and Z decrease because there is now more resistance ?

and for question 26 i saw that someone asked for the answer but nobody could answer it i have attached my answer (think it is right not sure though) correct me if its wrong. thanks for the help

for uncertanity, theres a simple rule, u ALWAYS add the uncertanities.
whenever there is ADDITION OR SUBTRACTION, u simply add the uncertanities
and whenevr there is division or multiplication, u add the fractional uncertanities.!!

 

[fatemakhan]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_13.pdf
Could someone please help me with Qs. 14, 15 and 33?

33:
overall R increases as now one resistor is in series wid 2 resistors in parallel
therefore overall I decreases....now watever the current is,X gets the whole of it while Y and Z get a half-half share,Thus, (since I is directly propotional to power keeping other factors constant) power to X increases whlie that to Y and Z decreases.(C)

 

[samwickz]

a) First off, bear in mind that since the 'same braking force' is used the acceleration is remaining constant. therefore first find the acc.
v^2 = 2as
10^2 = 2 x a x 10
a = 100/20=5
Now find the 's'
30^2 = 2 x 5 x 's'
s = 900/10 = 90 m

holy camoly thats not dat complicating @ all na woha thanx a bunch

 

[samwickz]

The frequency of a certain wave is 500Hz and its speed is 340ms–1
What is the phase difference between the motions of two points on the wave 0.17m apart?
A 4/πrad
B 2/πrad
C 4/3πrad
D π rad
YA IM STUCK AGAIN
so any body out there help me plz i kinda dont get d whole rad business @ all
btw the ans is B
HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!!!!!

 

[kinglynx]

right didnt really explain my questions which is what i needed, i can get the answers from a mark scheme....

 

[omg]

The frequency of a certain wave is 500Hz and its speed is 340ms–1
What is the phase difference between the motions of two points on the wave 0.17m apart?
A 4/πrad
B 2/πrad
C 4/3πrad
D π rad
YA IM STUCK AGAIN
so any body out there help me plz i kinda dont get d whole rad business @ all
btw the ans is B
HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!!!!!

i'll tell u a very easy method for solvin these typo qs,
remember, a path difference of lambda(one wavelength) = a phase difference of 2pi radians
from here we can form an equation , path diff/phase differnce=lamda/2pi radians
now find the wavelength from tha data given,
and substitute the values in the equation 2 get the phase difference!
hope that helpsss

 

[MysteRyGiRl]

i'll tell u a very easy method for solvin these typo qs,
remember, a path difference of lambda(one wavelength) = a phase difference of 2pi radians
from here we can form an equation , path diff/phase differnce=lamda/2pi radians
now find the wavelength from tha data given,
and substitute the values in the equation 2 get the phase difference!
hope that helpsss

radian here is? :S just da unit ryt?

 

[bloody_mary]

hey guys, I'm also having a little bit of trouble in the M/J p13 2011 paper (attached) with questions numbers:
4- pls explain this uncertainty stuff thoroughly as i don't get when to add, subtract, multiply etc. and if anyone has any notes on this pls upload them
12
27
33- I don't get this I understand that p=I^2R... what I did was just use a resistance of say 2 ohm's, in parallel the resistance would then be 1 ohm (of the parallel combination w and x) if w is removed then the resistance of x will be 2 ohm's correct? Is this the reason why the power to x increases? and the power to Y and Z decrease because there is now more resistance ?

and for question 26 i saw that someone asked for the answer but nobody could answer it i have attached my answer (think it is right not sure though) correct me if its wrong. thanks for the help

Q4
rules: when ever you are adding/subtracting 2 quantities always add absolute error
when ever you are multiplying/dividing 2 quantities always add percentage error
when you have a quantity to the power of something [eg 2] multiply percentage error by power [eg 2 *x% ]

so for distance falled 1 +1 =2
for time 0.02+0.02= 0.04

then find percentage error:
for distance 2/270
for time 0.04/2

then add both errors to get answer A

Q12
the weight is causing an anticlockwise moment on the ruler
so 0.6 * (0.02 *9.81) = 0.11772

weight of ruler is causing clockwise moment so 0.1 *( 0.1* 9.81) = 0.0981

therefore 0.05*9.81*x + 0.0981 = 0.11772 x= 0.04m (from pivot) which is 4cm so answer is 44cm

Q27
no clue at all

Q33
power is I^2R so proportional
and when you have 2 resistors in parallel the total resistance is less than individual resistance of each one so a higher resistance means more power across it and less across other components

and that person was me thanks a lot ♥♥

 

[omg]

radian here is? :S just da unit ryt?

yupsss!!

 

[bloody_mary]

hey guys, I'm also having a little bit of trouble in the M/J p13 2011 paper (attached) with questions numbers:
4- pls explain this uncertainty stuff thoroughly as i don't get when to add, subtract, multiply etc. and if anyone has any notes on this pls upload them
12
27
33- I don't get this I understand that p=I^2R... what I did was just use a resistance of say 2 ohm's, in parallel the resistance would then be 1 ohm (of the parallel combination w and x) if w is removed then the resistance of x will be 2 ohm's correct? Is this the reason why the power to x increases? and the power to Y and Z decrease because there is now more resistance ?

and for question 26 i saw that someone asked for the answer but nobody could answer it i have attached my answer (think it is right not sure though) correct me if its wrong. thanks for the help

just one question how did you get x and z to be 45 degrees? :S

 

[Sana101]

The frequency of a certain wave is 500Hz and its speed is 340ms–1
What is the phase difference between the motions of two points on the wave 0.17m apart?
A 4/πrad
B 2/πrad
C 4/3πrad
D π rad
YA IM STUCK AGAIN
so any body out there help me plz i kinda dont get d whole rad business @ all
btw the ans is B
HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!!!!!

a) first find the wavelength = speed/frequency
= 340/500 = 0.68m
Formula for path difference (you need to know this) = 2(pie) x path difference (which is 0.17 in this case) / wavelength(0.68)
= 2(pie) x 0.17 / 0.68 = 1/2(pie)