Biology; Chemistry; Physics: Post your doubts here!

[Dashing Cancerian]

http://www.xtremepapers.com/papers/CIE/Cambridge International O Level/Physics (5054)/5054_w09_qp_1.pdf
1, 4, 11, 22, 28, 37 , 39 ??

for 4... its 4 as 12/3= 4 m/s it says from rest so.... 12-0
for 11.... it would be A cox volume is inversely propotional to pressure...

 

[malay]

http://www.xtremepapers.com/papers/CIE/Cambridge International O Level/Physics (5054)/5054_s07_qp_1.pdf
39 ??

i think its C coz gamma rays being neutral r not deflected and hence r detected
do tell the corect ans

 

[convent2012]

for 4... its 4 as 12/3= 4 m/s it says from rest so.... 12-0
for 11.... it would be A cox volume is inversely propotional to pressure...

thanks

 

[syed1995]

Because if they said the frictional orce on the car thn it would have been B but they said the wheel so it will be D !

why is the friction force for the wheel different??

 

[Dashing Cancerian]

thanks

anytym nd i havent studied the other topics

 

[Mayedah]

i think its C coz gamma rays being neutral r not deflected and hence r detected
do tell the corect ans

Itll be B ! Because a beta particle is deflected out of the plane of magnetic field if it passes thru it perpendicualrly according to flemings left hand rule !

 

[asd]

why is the friction force for the wheel different??

roll your pen on the floor and see its movement, although it would move forward it would be rotating in the opposite direction! that's why.

 

[convent2012]

i think its C coz gamma rays being neutral r not deflected and hence r detected
do tell the corect ans

no its beta particles but why ??

 

[Mayedah]

no its beta particles but why ??

Itll be B ! Because a beta particle is deflected out of the plane of magnetic field if it passes thru it perpendicualrly according to flemings left hand rule !

 

[convent2012]

Itll be B ! Because a beta particle is deflected out of the plane of magnetic field if it passes thru it perpendicualrly according to flemings left hand rule !

thanku

 

[khizer shahab]

http://www.xtremepapers.com/papers/...nal O Level/Physics (5054)/5054_s10_qp_11.pdf

q6 with reason..
q 8 with explanation !! please
q13,q16,q28

 

[kitecrystal]

9 is A because the increase in load is shared between two springs.
26 is D beacuse iron magnetizes and demagenetises quickly
33 is C use L.H.R
37 is B because when resistence increase less current flows thus the capacitor discharges very slowly
40 is A because Alpha Particles go straight pass the foil!

thanku

 

[Ahmedfj]

need help in mcq 27 june 2006 physics

 

[Mayedah]

for 4... its 4 as 12/3= 4 m/s it says from rest so.... 12-0
for 11.... it would be A cox volume is inversely propotional to pressure...

And the answer to this will not be four its six baecause average speed is the distance / time so first u have to take out distance which will come 18 thn divide it by tym so ull get 6 !

 

[Dashing Cancerian]

And the answer to this will not be four its six baecause average speed is the distance / time so first u have to take out distance which will come 18 thn divide it by tym so ull get 6 !

forgot that

 

[kitecrystal]

Left hand rule. If the question states that magnetic field is out of the page/into the page, you'll have to give you answer with respect to top/bottom of the page.
For protons (carrying positive charge) the direction of the current will be the same as shown. For eg: Field is into the page (x)(x)(x)(x)(x), and the alpha particles/protons are released from left to right, from flehming's left hand rule, they will divert to the top of the page.
Your middle finger ( ) to the right ----> for alpha particles, and your first finger towards the floor (for field which is into the page). You will see your thumb pointing forwards, which depicts they will divert to the top of the page.
For electrons/beta-particles, point your middle finger to the opposite side of the direction shown (for the particles), because the electrons carry -ve charge (opposite to that of protons)

plz also explain how we can use left hand rule here in q33.

 

[Mayedah]

http://www.xtremepapers.com/papers/...nal O Level/Physics (5054)/5054_s10_qp_11.pdf

q6 with reason..
q 8 with explanation !! please
q13,q16,q28

Q6 bcuz thre is always a force towards the centre When ny object is moving in a circle so D

 

[Mayedah]

plz also explain how we can use left hand rule here in q33.

U dnt have to use left hand rule in this u have to use right hand rule for current and direction of magnetic field !

 

[syed1995]

I would go with A .. cuz of microwave oven .. is it correct? but what would be the logical approach?

 

[Dashing Cancerian]

http://www.xtremepapers.com/papers/CIE/Cambridge International O Level/Physics (5054)/5054_s10_qp_11.pdf

q6 with reason..
q 8 with explanation !! please
q13,q16,q28

Q8 fxd=fxd
so, 30 x weight=(30+30) x 15
weight=60 x 15/30
=30 N now change it to mass by W=mg
30/10= 3 kg