Physics Paper 1 question!

[$$AK$$]

could you post the link of the paper

i dont have the link,but i can attach the pdf file

btw which years you advice me to do

 

[$$AK$$]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_w07_qp_1.pdf
Q23 i dont understand it ?

I think that the answer is c,yes
if yes then the disttance from the new position of the object to the mirror should be equal to the distance from the mirror to the tip of the arrow of A,B,C,or D so if you mesured it then you will find that the answer is C
do you understamd??
I hope so

 

[Sapphire_26]

M/J 2007 question 12, why is the answer B???
http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s07_qp_1.pdf

 

[Othman]

M/J 2007 question 12, why is the answer B???
http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s07_qp_1.pdf

The density of the new liquid is more, so the change in height (h) is small compared with the h in the water, for that reason water is used ( or less dense liquids) in manometers where a small pressure change is present.

 

[cookiemaker]

The pressure to be measured is the same. Pressure is calculated by pgh. So if the liquid is more dense, p would increase meaning h has to decrease

 

[Sapphire_26]

The density of the new liquid is more, so the change in height (h) is small compared with the h in the water, for that reason water is used ( or less dense liquids) in manometers where a small pressure change is present.

I m sorry bt i really can't understand, can u explain it in a way that is a little less complex??
thankx

 

[Sapphire_26]

The pressure to be measured is the same. Pressure is calculated by pgh. So if the liquid is more dense p would increase meaning h has to decrease

how do u know that pressure is same???

 

[cookiemaker]

how do u know that pressure is same???

Its a pressure to be measured, for example in the air. It wont change by changing the liquid. I think it is the same.

 

[Yashagrawal57]

Hi guys, I have a doubt in one of the physics paper 1:

W12, QP12, Q16
A boy sits near a campfire. He pokes the fire with an iron bar. His hand becomes hot.
In which ways does thermal energy (heat) from the fire reach his hand?

A conduction and convection only
B conduction and radiation only
C convection and radiation only
D conduction, convection and radiation

The answer given is B. But shouldn't it be D, because the fire also heats up the air, which creates convection currents, reaching the boy's hand??

 

[Sapphire_26]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s07_qp_1.pdf
question 17. how can the answer possibly radiation (D)?? shouldn't it be convection?? I mean there is still air present.. right

 

[Vibhs08]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s07_qp_1.pdf
question 17. how can the answer possibly radiation (D)?? shouldn't it be convection?? I mean there is still air present.. right

the bread is heated by electromagnetic waves radiated by the heating element. hence the answer is radiation.
hope this solves your doubt.

 

[Vibhs08]

Hi guys, I have a doubt in one of the physics paper 1:

W12, QP12, Q16
A boy sits near a campfire. He pokes the fire with an iron bar. His hand becomes hot.
In which ways does thermal energy (heat) from the fire reach his hand?

A conduction and convection only
B conduction and radiation only
C convection and radiation only
D conduction, convection and radiation

The answer given is B. But shouldn't it be D, because the fire also heats up the air, which creates convection currents, reaching the boy's hand??

u need to consider how the heat is transferd from the iron bar to the hand and not the overall effect.

 

[Sapphire_26]

the bread is heated by electromagnetic waves radiated by the heating element. hence the answer is radiation.
hope this solves your doubt.

but how do u know that "the bread is heated by electromagnetic waves radiated by the heating element"
i mean it isn't mentioned anywhere in the question!!

 

[Vibhs08]

but how do u know that "the bread is heated by electromagnetic waves radiated by the heating element"
i mean it isn't mentioned anywhere in the question!!

it's becuz electromagnetic waves are used to create the heating effect in microwave ovens.
so it's obvious that the heating element shown in the diagram, radiates electromagnetic waves.
hence, the answer is D.

 

[oahmed64]

guys im getting really confused now about forces
if two forces act in the same direction can they be in equilibrium ?
also there was a question about a wood stick that is pivoted and free to move and three forces of the same value are acting on it in different directions and the question was in which direction does the wood move ? how do we know the answer ?

 

[cookiemaker]

guys im getting really confused now about forces
if two forces act in the same direction can they be in equilibrium ?
also there was a question about a wood stick that is pivoted and free to move and three forces of the same value are acting on it in different directions and the question was in which direction does the wood move ? how do we know the answer ?

By the resultant force which is calculated by subtraction.

For example if there is a 6 N force to the left and a 4 N force to the right, the resultant force would be 2 N to the left (6-4)

A link to the paper that you are solving would be useful.

 

[salma_69]

A metal wire, initially 1.000m long, extends by 4mm when a load of 2N is added to it.
What will the length of the wire be if a further 3N is added, assuming it does not extend beyond
its limit of proportionality?

A 1.060m
B 1.080m
C 1.010m
D 1.012m
plz help me in this question...

 

[Sapphire_26]

A metal wire, initially 1.000m long, extends by 4mm when a load of 2N is added to it.
What will the length of the wire be if a further 3N is added, assuming it does not extend beyond
its limit of proportionality?

A 1.060m
B 1.080m
C 1.010m
D 1.012m
plz help me in this question...

It's C, I think

 

[Sapphire_26]

it's becuz electromagnetic waves are used to create the heating effect in microwave ovens.
so it's obvious that the heating element shown in the diagram, radiates electromagnetic waves.
hence, the answer is D.

you have no idea how dumb i feel after this... I am oblivious to the most obvious thing!!

 

[Sapphire_26]

1st u wrote D...........
BTW C is the correct answer

*self hi-5*
and yea i wrote D by mistake...