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Physics, Chemistry and Biology: Post your doubts here!

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Yeah, the slight chance that they do end up asking a question about those.. its usually worth alot of marks :S
It's not THAT much of a slight chance, seen it several times nad it's stated CLEARLY in the syllabus. I mean seriously, should honestly know this stuff by now :p
 
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due 2 a magnetic field, r beta particles deflected in d opp direction or in the same? plz reply ASAP
 
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Left hand? I only know about the right hand rule; either way, I still can't figure it out :(
And what about number 10 a) and b).
How do we draw the graph annnnd you said to increase the voltage, but they want it halved? Why is it not the other way around?
:cry:So confused...
left hand rule is used when the current is given and u have to find the direction of the force/direction of magnetic field. so if u put it that way the thumb is the direction of force, fore finger is the magnetic field and middle finger is the direction of flow of current. According to that question, u use your left hand and poin the thumb to the left and ur middle finger should be pointin downwards (direction of flow of current is opposite to direction of flow of electrons and since beta particle is just electron) u should get the magnetic field to point into the page


and for 10 a) and b)
a) the frequency is increased by 1.5 times
first you find the time for one wave by counting the no. of boxes in one wave
then u find the frequency using F=1/T where F is frequecy and T is time for one wave
then u multiply this into 1.5 to get the new frequency
then u find the time for the new wave by the same formula, just shift places T=1/F
u get the time for one wave with the frequency increased by 1.5 times
draw this

b) they want the height of the peak to become half
the voltage gain is 5/cm
currently, the peak is 15V and it occupies 3cm
u want to make it occupy 1.5cm
so u increase the voltage gain exactly twice the previous
now it has become 10V/cm,
and since the peak is 15V it will occupy 1.5cm according to the new scale

hope it helped :)
 
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Hey thatreallyreallyweirddude could u quiz me on like some hard querstions? Thx
Sorry but no :p I'm fine with answering questions but don't have time to do what you ask for. Sorry!
due 2 a magnetic field, r beta particles deflected in d opp direction or in the same? plz reply ASAP
A stream of beta particles is like current (it's a line of moving electrons in the end)
So to know the change in direction you use fleming's left hand rule
just remember that since the beta particles are a stream of electrons, you have to use it backwards since conventional current is opposite to flow of electrons.
I.e. if beta particles are going to the right, you should point your second finger to left.
 
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left hand rule is used when the current is given and u have to find the direction of the force/direction of magnetic field. so if u put it that way the thumb is the direction of force, fore finger is the magnetic field and middle finger is the direction of flow of current. According to that question, u use your left hand and poin the thumb to the left and ur middle finger should be pointin downwards (direction of flow of current is opposite to direction of flow of electrons and since beta particle is just electron) u should get the magnetic field to point into the page


and for 10 a) and b)
a) the frequency is increased by 1.5 times
first you find the time for one wave by counting the no. of boxes in one wave
then u find the frequency using F=1/T where F is frequecy and T is time for one wave
then u multiply this into 1.5 to get the new frequency
then u find the time for the new wave by the same formula, just shift places T=1/F
u get the time for one wave with the frequency increased by 1.5 times
draw this

b) they want the height of the peak to become half
the voltage gain is 5/cm
currently, the peak is 15V and it occupies 3cm
u want to make it occupy 1.5cm
so u increase the voltage gain exactly twice the previous
now it has become 10V/cm,
and since the peak is 15V it will occupy 1.5cm according to the new scale

hope it helped :)
which question r u talkin abt ? :/
 
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i think smthg is wrong here cux even i was confused! but now they r like peak to peak mean amplitude ;/
See:
Peak voltage. When the gain control is 5 V/cm it means that each cm represents 5 Volts. Now if the amplitude of the wave is 2 cm. The peak and highest voltage should be 10 V. 5 x 2=10
 
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See:
Peak voltage. When the gain control is 5 V/cm it means that each cm represents 5 Volts. Now if the amplitude of the wave is 2 cm. The peak and highest voltage should be 10 V. 5 x 2=10
well yes that's ok i am just askin what is peak to peak height? is it for x plates or y?
 
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Time base setting should be the same but the other one should be 2V per cm instead of 1V per cm.....thats what I think.....Im not sure....
 
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And for Period. Period means the time taken for 1 complete cycle of a wave. Time base is actually controlled by the X-plate. If the time base is 10 ms/cm. It means that the spot takes 10 ms to move 1 cm. It basically means 1 cm= 10 ms. Now if the peak to peak distance is 4 cm. Then the time should be 4 x 10. Which is 40 ms.
 
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