A few things for Physics MCQ to remember (points that people usually forget or don't know at all)

[Doggybros]

Ok, just some things you dont normally find in books, or some things that will help you do your calculations without calculating anything.
People usually forget these things, and some dont know them at all
(Sorry the lambda symbol looks cranky, just couldnt find the real one)

In a closed pipe,
Wavelengths that fit in are all odd multiples of ƛ/4
For nth node, frequency is fn = (2n-1)f1 where n = 1,2,3,4 and so on....
where f1 is the frequency of the lowermost node ie ƛ/4 (See below if you dont understand nodes)

(If you don't know what a node is:
1st node is the one where ƛ/4 fits in.
2nd node is the one where 2ƛ/4 fits in.
3rd node is the one where 3ƛ/4 fits in. its different in open pipe, im giving the formula)

In an open pipe,
Wavelengths that fit in are all multiples of ƛ/2.
So there is ƛ/2, 2ƛ/2, 3ƛ/2, 4ƛ/2 and so on.

For nth node, frequency is: fn = nf1

(IMPORTANT!!!!)
Formula of phase difference: 2π/ƛ × x WHERE ƛ is the wavelength and x is the path difference.
In case you are super noob in physics go look up path difference, I'm not going into that.

Common wavelengths:
Gamma: 0.01 nm
X ray: 0.1 nm
UV ray: 30 nm
Visible: Violet: 400nm
Green: 500nm
Orange: 600 nm
Red: 700 nm
Infra red: 10 micrometers
Anything greater than 100 micrometers is radio wave


Symbol of a fuse is the one where the circuit wire goes through a rectangular box.
Symbol of a LDR is the one where two arrows are pointing to the box.
Symbol of a thermistor is the one where a line passes almost diagonally across a box and has a small extension at the bottom.
NOT TO BE CONFUSED with symbol of a variable resistor, an arrow passing almost diagonally through a box.

When there is no current, electrons move about randomly and when there is current, electrons move from negative terminal to positive.

For a case where two resistors are in series (usually potentiometer):
When resistance of one decreases, Voltage across it decreases and the voltage across the another increases.
Vice versa for increase in resistance.
(You can calculate in the exam but remembering this line helps you save some valuable time)

In a parallel circuit, Voltage across resistors is constant, so more resistance means less current, to maintain equal voltage.
In a series circuit, current across resistors is constant, so more resistance means more voltage.

pd is always less than emf because energy is needed to drive charge through cell.

When reaching terminal velocity, air resistance increases to a constant value.


For nuclear physics:
Diameter of an atom is in the order 10^-10
Diameter of a nucleus is in the order 10^-15

A question similar to this has been asked many times:
When same voltage is applied to each of the following nuclei, which reaches the highest velocity?

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

REMEMBER THESE POINTS AND I'M SURE I WILL HAVE HELPED YOU WITH 5-10 MARKS.
THAT'S ALL FOLKS!!!!
Hope I rang a bell in your head or at least told you something you didn't know.
DONT MOCK ME IF NONE OF THIS HELPED.
NOTHING WRITTEN ABOVE IS WRONG, I CAN VERIFY THAT.

 

[JalalKaiser]

I shall love you forever for this. You're a life-saver. JazakAllah Khair. =P

 

[Doggybros]

Sorry I didn't explain what the frequency thing in the first question clearly enough, I realized it after I read it myself.
The question will be like: In an open pipe, a resonance(or some other similar word, i forgot) is produced when a wave of frequency of 100 hz is applied. What is the next higher frequency to be used to produce resonance?
So f1 is given and you just have to calculate f2 using the formula I gave you(which is different to open pipe or closed ones).
I realized I had written it too confusing, what with nodes and all.

 

[thunderingthunder]

Thank you very very much Doggybros....you really have proved to be a life-safer

 

[Diva#1]

Ok, just some things you dont normally find in books, or some things that will help you do your calculations without calculating anything.
People usually forget these things, and some dont know them at all
(Sorry the lambda symbol looks cranky, just couldnt find the real one)

In a closed pipe,
Wavelengths that fit in are all odd multiples of ƛ/4
For nth node, frequency is fn = (2n-1)f1 where n = 1,2,3,4 and so on....
where f1 is the frequency of the lowermost node ie ƛ/4 (See below if you dont understand nodes)

(If you don't know what a node is:
1st node is the one where ƛ/4 fits in.
2nd node is the one where 2ƛ/4 fits in.
3rd node is the one where 3ƛ/4 fits in. its different in open pipe, im giving the formula)

In an open pipe,
Wavelengths that fit in are all multiples of ƛ/2.
So there is ƛ/2, 2ƛ/2, 3ƛ/2, 4ƛ/2 and so on.

For nth node, frequency is: fn = nf1

(IMPORTANT!!!!)
Formula of phase difference: 2π/ƛ × x WHERE ƛ is the wavelength and x is the path difference.
In case you are super noob in physics go look up path difference, I'm not going into that.

Common wavelengths:
Gamma: 0.01 nm
X ray: 0.1 nm
UV ray: 30 nm
Visible: Violet: 400nm
Green: 500nm
Orange: 600 nm
Red: 700 nm
Infra red: 10 micrometers
Anything greater than 100 micrometers is radio wave


Symbol of a fuse is the one where the circuit wire goes through a rectangular box.
Symbol of a LDR is the one where two arrows are pointing to the box.
Symbol of a thermistor is the one where a line passes almost diagonally across a box and has a small extension at the bottom.
NOT TO BE CONFUSED with symbol of a variable resistor, an arrow passing almost diagonally through a box.

When there is no current, electrons move about randomly and when there is current, electrons move from negative terminal to positive.

For a case where two resistors are in series (usually potentiometer):
When resistance of one decreases, Voltage across it decreases and the voltage across the another increases.
Vice versa for increase in resistance.
(You can calculate in the exam but remembering this line helps you save some valuable time)

In a parallel circuit, Voltage across resistors is constant, so more resistance means less current, to maintain equal voltage.
In a series circuit, current across resistors is constant, so more resistance means more voltage.

pd is always less than emf because energy is needed to drive charge through cell.

When reaching terminal velocity, air resistance increases to a constant value.


For nuclear physics:
Diameter of an atom is in the order 10^-10
Diameter of a nucleus is in the order 10^-15

A question similar to this has been asked many times:
When same voltage is applied to each of the following nuclei, which reaches the highest velocity?

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

REMEMBER THESE POINTS AND I'M SURE I WILL HAVE HELPED YOU WITH 5-10 MARKS.
THAT'S ALL FOLKS!!!!
Hope I rang a bell in your head or at least told you something you didn't know.
DONT MOCK ME IF NONE OF THIS HELPED.
NOTHING WRITTEN ABOVE IS WRONG, I CAN VERIFY THAT.

Thank you sooo much for these notes...They helped alot

 

[XPFMember]

Doggybros Thanks a lot! that was helpful...

 

[1357913579]

Ok, just some things you dont normally find in books, or some things that will help you do your calculations without calculating anything.
People usually forget these things, and some dont know them at all
(Sorry the lambda symbol looks cranky, just couldnt find the real one)

In a closed pipe,
Wavelengths that fit in are all odd multiples of ƛ/4
For nth node, frequency is fn = (2n-1)f1 where n = 1,2,3,4 and so on....
where f1 is the frequency of the lowermost node ie ƛ/4 (See below if you dont understand nodes)

(If you don't know what a node is:
1st node is the one where ƛ/4 fits in.
2nd node is the one where 2ƛ/4 fits in.
3rd node is the one where 3ƛ/4 fits in. its different in open pipe, im giving the formula)

In an open pipe,
Wavelengths that fit in are all multiples of ƛ/2.
So there is ƛ/2, 2ƛ/2, 3ƛ/2, 4ƛ/2 and so on.

For nth node, frequency is: fn = nf1

(IMPORTANT!!!!)
Formula of phase difference: 2π/ƛ × x WHERE ƛ is the wavelength and x is the path difference.
In case you are super noob in physics go look up path difference, I'm not going into that.

Common wavelengths:
Gamma: 0.01 nm
X ray: 0.1 nm
UV ray: 30 nm
Visible: Violet: 400nm
Green: 500nm
Orange: 600 nm
Red: 700 nm
Infra red: 10 micrometers
Anything greater than 100 micrometers is radio wave


Symbol of a fuse is the one where the circuit wire goes through a rectangular box.
Symbol of a LDR is the one where two arrows are pointing to the box.
Symbol of a thermistor is the one where a line passes almost diagonally across a box and has a small extension at the bottom.
NOT TO BE CONFUSED with symbol of a variable resistor, an arrow passing almost diagonally through a box.

When there is no current, electrons move about randomly and when there is current, electrons move from negative terminal to positive.

For a case where two resistors are in series (usually potentiometer):
When resistance of one decreases, Voltage across it decreases and the voltage across the another increases.
Vice versa for increase in resistance.
(You can calculate in the exam but remembering this line helps you save some valuable time)

In a parallel circuit, Voltage across resistors is constant, so more resistance means less current, to maintain equal voltage.
In a series circuit, current across resistors is constant, so more resistance means more voltage.

pd is always less than emf because energy is needed to drive charge through cell.

When reaching terminal velocity, air resistance increases to a constant value.


For nuclear physics:
Diameter of an atom is in the order 10^-10
Diameter of a nucleus is in the order 10^-15

A question similar to this has been asked many times:
When same voltage is applied to each of the following nuclei, which reaches the highest velocity?

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

REMEMBER THESE POINTS AND I'M SURE I WILL HAVE HELPED YOU WITH 5-10 MARKS.
THAT'S ALL FOLKS!!!!
Hope I rang a bell in your head or at least told you something you didn't know.
DONT MOCK ME IF NONE OF THIS HELPED.
NOTHING WRITTEN ABOVE IS WRONG, I CAN VERIFY THAT.

ASSALAMOALIKUM
thanks bro,
is this formula in our syllabus, f=1/2t(T/MASS PER UNIT LENTH)
for finding the fundemental frequency?

 

[biba]

Ok, just some things you dont normally find in books, or some things that will help you do your calculations without calculating anything.
People usually forget these things, and some dont know them at all
(Sorry the lambda symbol looks cranky, just couldnt find the real one)

In a closed pipe,
Wavelengths that fit in are all odd multiples of ƛ/4
For nth node, frequency is fn = (2n-1)f1 where n = 1,2,3,4 and so on....
where f1 is the frequency of the lowermost node ie ƛ/4 (See below if you dont understand nodes)

(If you don't know what a node is:
1st node is the one where ƛ/4 fits in.
2nd node is the one where 2ƛ/4 fits in.
3rd node is the one where 3ƛ/4 fits in. its different in open pipe, im giving the formula)

In an open pipe,
Wavelengths that fit in are all multiples of ƛ/2.
So there is ƛ/2, 2ƛ/2, 3ƛ/2, 4ƛ/2 and so on.

For nth node, frequency is: fn = nf1

(IMPORTANT!!!!)
Formula of phase difference: 2π/ƛ × x WHERE ƛ is the wavelength and x is the path difference.
In case you are super noob in physics go look up path difference, I'm not going into that.

Common wavelengths:
Gamma: 0.01 nm
X ray: 0.1 nm
UV ray: 30 nm
Visible: Violet: 400nm
Green: 500nm
Orange: 600 nm
Red: 700 nm
Infra red: 10 micrometers
Anything greater than 100 micrometers is radio wave


Symbol of a fuse is the one where the circuit wire goes through a rectangular box.
Symbol of a LDR is the one where two arrows are pointing to the box.
Symbol of a thermistor is the one where a line passes almost diagonally across a box and has a small extension at the bottom.
NOT TO BE CONFUSED with symbol of a variable resistor, an arrow passing almost diagonally through a box.

When there is no current, electrons move about randomly and when there is current, electrons move from negative terminal to positive.

For a case where two resistors are in series (usually potentiometer):
When resistance of one decreases, Voltage across it decreases and the voltage across the another increases.
Vice versa for increase in resistance.
(You can calculate in the exam but remembering this line helps you save some valuable time)

In a parallel circuit, Voltage across resistors is constant, so more resistance means less current, to maintain equal voltage.
In a series circuit, current across resistors is constant, so more resistance means more voltage.

pd is always less than emf because energy is needed to drive charge through cell.

When reaching terminal velocity, air resistance increases to a constant value.


For nuclear physics:
Diameter of an atom is in the order 10^-10
Diameter of a nucleus is in the order 10^-15

A question similar to this has been asked many times:
When same voltage is applied to each of the following nuclei, which reaches the highest velocity?

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

REMEMBER THESE POINTS AND I'M SURE I WILL HAVE HELPED YOU WITH 5-10 MARKS.
THAT'S ALL FOLKS!!!!
Hope I rang a bell in your head or at least told you something you didn't know.
DONT MOCK ME IF NONE OF THIS HELPED.
NOTHING WRITTEN ABOVE IS WRONG, I CAN VERIFY THAT.

excellent! thanx alot!

 

[XPFMember]

Assalamoalaikum wr wb!

Another thing...for an I-V graph, if it's a curve, remember resistance is NOT the gradient of the graph! U have to take read-offs from the graph at that particular point and calculate the resistance!

 

[hychristine]

dude thx soooooooo much for this!!! u saved me!!!

 

[mursallini]

Ok, just some things you dont normally find in books, or some things that will help you do your calculations without calculating anything.
People usually forget these things, and some dont know them at all
(Sorry the lambda symbol looks cranky, just couldnt find the real one)

In a closed pipe,
Wavelengths that fit in are all odd multiples of ƛ/4
For nth node, frequency is fn = (2n-1)f1 where n = 1,2,3,4 and so on....
where f1 is the frequency of the lowermost node ie ƛ/4 (See below if you dont understand nodes)

(If you don't know what a node is:
1st node is the one where ƛ/4 fits in.
2nd node is the one where 2ƛ/4 fits in.
3rd node is the one where 3ƛ/4 fits in. its different in open pipe, im giving the formula)

In an open pipe,
Wavelengths that fit in are all multiples of ƛ/2.
So there is ƛ/2, 2ƛ/2, 3ƛ/2, 4ƛ/2 and so on.

For nth node, frequency is: fn = nf1

(IMPORTANT!!!!)
Formula of phase difference: 2π/ƛ × x WHERE ƛ is the wavelength and x is the path difference.
In case you are super noob in physics go look up path difference, I'm not going into that.

Common wavelengths:
Gamma: 0.01 nm
X ray: 0.1 nm
UV ray: 30 nm
Visible: Violet: 400nm
Green: 500nm
Orange: 600 nm
Red: 700 nm
Infra red: 10 micrometers
Anything greater than 100 micrometers is radio wave


Symbol of a fuse is the one where the circuit wire goes through a rectangular box.
Symbol of a LDR is the one where two arrows are pointing to the box.
Symbol of a thermistor is the one where a line passes almost diagonally across a box and has a small extension at the bottom.
NOT TO BE CONFUSED with symbol of a variable resistor, an arrow passing almost diagonally through a box.

When there is no current, electrons move about randomly and when there is current, electrons move from negative terminal to positive.

For a case where two resistors are in series (usually potentiometer):
When resistance of one decreases, Voltage across it decreases and the voltage across the another increases.
Vice versa for increase in resistance.
(You can calculate in the exam but remembering this line helps you save some valuable time)

In a parallel circuit, Voltage across resistors is constant, so more resistance means less current, to maintain equal voltage.
In a series circuit, current across resistors is constant, so more resistance means more voltage.

pd is always less than emf because energy is needed to drive charge through cell.

When reaching terminal velocity, air resistance increases to a constant value.


For nuclear physics:
Diameter of an atom is in the order 10^-10
Diameter of a nucleus is in the order 10^-15

A question similar to this has been asked many times:
When same voltage is applied to each of the following nuclei, which reaches the highest velocity?

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

REMEMBER THESE POINTS AND I'M SURE I WILL HAVE HELPED YOU WITH 5-10 MARKS.
THAT'S ALL FOLKS!!!!
Hope I rang a bell in your head or at least told you something you didn't know.
DONT MOCK ME IF NONE OF THIS HELPED.
NOTHING WRITTEN ABOVE IS WRONG, I CAN VERIFY THAT.

thnx this really helped out but can u plzz tell me how u find the path difference?

 

[JalalKaiser]

Assalamoalaikum wr wb!

Another thing...for an I-V graph, if it's a curve, remember resistance is NOT the gradient of the graph! U have to take read-offs from the graph at that particular point and calculate the resistance!

For this question, find the ratio of charge to mass. It is directly proportional to velocity and you can equate it to velocity for your convenience in the exams.

How exactly are we supposed to do these two things btw?

Sorry, complete dunce here.

 

[XPFMember]

How exactly are we supposed to do these two things btw?

Sorry, complete dunce here.

Assalamoalaikum wr wb!
I mean, if you're given a graph of I-V and it's a curve , say u want to find the resistance at , say 8 V , then using the graph check out the corresponding value of current and use the formula R=V/I .....don't attempt to draw a tangent n find the gradient....

 

[JalalKaiser]

Assalamoalaikum wr wb!
I mean, if you're given a graph of I-V and it's a curve , say u want to find the resistance at , say 8 V , then using the graph check out the corresponding value of current and use the formula R=V/I .....don't attempt to draw a tangent n find the gradient....

Oh, alriiight. Thank you so very much.

 

[Doggybros]

Assalamoalaikum wr wb!

Another thing...for an I-V graph, if it's a curve, remember resistance is NOT the gradient of the graph! U have to take read-offs from the graph at that particular point and calculate the resistance!

I think the reciprocal of the gradient of the tangent is the resistance, you cannot just use one point.

 

[Doggybros]

How exactly are we supposed to do these two things btw?

Sorry, complete dunce here.

Just count the number of protons and neutrons. The number of protons is the charge, number of protons+neutrons is the mass. What kind of school did u study in? LOL

 

[Doggybros]

thnx this really helped out but can u plzz tell me how u find the path difference?

LOL you do not know path diff?
Its simple though.
Two points on the wave curve will be given. Just count the number of wavelengths the point has travelled and subtract it from the other one.

 

[i love my country]

that is great really thanx ...

 

[JalalKaiser]

Just count the number of protons and neutrons. The number of protons is the charge, number of protons+neutrons is the mass. What kind of school did u study in? LOL

School's good enough but my teacher pretty much sucked. :|

 

[Doggybros]

School's good enough but my teacher pretty much sucked. :|

That's your problem? We had three teachers, and all three sucked.