I hear that exam season and starting up in India. So, for my Indian viewers who may already be
well-acquainted with the exam I'm going to show today,
hopefully this video may save you a quick revision of some of the topics that are involved,
and a reminder of what's in the syllabus and what you're expected to know.
For my viewers who are not in India,
let this video be a quick glimpse into what our Indian friends have to go through.
Today, I'm going to be looking at the JEE Main exam.
Now, I've covered the JEE Advanced exam before on my channel.
So, I guess this is winding back a step to the Main exam, which is used as an entrance exam
into some of India's colleges.
This exam here is Paper Number 1 from 2018.
I believe that in 2019 the exams are going to be held online;
you're not going to be able to have a calculator. And there's over a million candidates who sit this exam.
I do also believe that the syllabus doesn't change from year to year.
So, hopefully the questions that we'll look at today,
and the topics that are involved are still going to be relevant into the future.
I'm really just going to talk about the physics section in this video, because physics is my area.
There is also math and chemistry components to this exam,
but let's first just have a look at the physics section.
You get three hours to do the entire exam, so that's probably one hour per section.
And I've made a few notes on these physics problems, whether it's formula or basic ideas
that you're going to need to know to get started solving the problem.
But I obviously haven't written down everything that you're going to need to solve them.
And there's no time in this video to solve every question.
But, let's just have a look at what components of the syllabus each question covers.
So, we're starting off with a question about energy and momentum, specifically about collisions.
This question uses the idea of conservation of momentum.
Then, we go on to heat and thermodynamics, and a question about the kinetic theory of gases.
Here, you're working with the change in momentum and with pressure.
Question three, we're dealing with properties of matter, in terms of elasticity.
And, I've written down here the formula for the bulk modulus,
which is what you're going to need to get started here.
Also, you're going to need a relationship between volume and radius.
Number four is about DC Circuit's, and about working out an equivalent resistance and voltage.
Question five is about energy and momentum including potential energy.
So I've written down a few formulas here like centripetal force,
and working out total energy from potential and kinetic.
Number six, we're dealing with the dynamics questions. So we've got, we need to know concepts about friction.
So, there's one little formula I've put here, and it's a pulley system.
So knowing the threshold of force, which is related to the coefficient of friction and the normal force.
Going on to question seven.
We're dealing with, I guess modern physics as it's still classed on the syllabus and dealing with atoms.
I think we're probably going to need to do some manipulation of the Rydberg equation here.
So, I've got that written there.
Number eight is waves and optics, so dealing with polarizing filters.
Question nine, another problem about modern physics and atoms.
You're going to need to in this question use the binomial expansion,
because you're dealing with large values of 'n'.
We've then got a question about semiconductors or diodes.
And essentially for this question, I was surprised that you need to have memorized or know that
a silicon diode is taking a voltage of 0.7 volts when used in the forwards direction.
Other than knowing that, you need to use I equals V over R (I = V/R) to work out number 10.
Question 11 is about magnetism and the force on a moving charge.
So, it's useful to know this equation here
which is to do with working out the radius of an orbit, a circular orbit of a charge
which has a force opponent.
Number 12 is about capacitors and dielectrics.
So, having some relation between dielectrics and the total charge which is stored.
Number 13. This time we have an AC Circuit. And you need to know about what's called a Quality factor.
For question 14, it's about communication systems and bandwidth.
So, they're asking us about the number of telephonic channels.
And that would be given by the total bandwidth over the channel bandwidth of each channel.
So, that gives us our answer out there.
Number 15 is to do with waves and resonance.
So, it's useful to be able to relate some of the basic properties of waves, like speed and wavelength
to some slightly harder concepts like the young's modulus here.
Number 16 is quite a tricky question, I think about moments of inertia and to do with a rotating object.
So, I guess really needing to skill up on how to find moments of inertia
for what is a semi-complicated shape even though it is symmetrical.
You also for this one,
I think it's useful to know the parallel axis theorem and use it along this axis here.
Number 17 is about what's called electrostatics.
So, probably useful to know how to find the potential of a point charge at any radius away from it.
Number 18 is another one about DC Circuits. This time it's about something called a Potentiometer.
I'm not really that confident with those, but hopefully maybe you've done a few
practices with one of those. I think in the end it comes down to comparing the cases that it gives you.
Number 19 is about electromagnetic waves and the speed of a wave.
Number 20 is about waves too, but this is about like waves and optics
and it's talking about single slit diffraction, which is useful to know the angular width of a central maximum
in single slit diffraction, which is as here.
And it's also talking about Young's double slit experiments.
So similarly, we have a little bit of help here. We can remember some of these formulas.
Number 21, we're looking at simple harmonic motion - a classic in physics.
So, hopefully you've got a bit of practice with that.
Number 22 is about rotation and again moments of inertia. I often find these moments of inertia questions a bit tricky.
Number 23 is about energy and momentum. We have a collision.
And again, one of the fundamental concepts will be that momentum is conserved
as there are no external forces acting here.
Number 24 is about magnetism. And we've got our classic formula here
for finding the strength of the magnetic field.
25. This one is actually to do with like uncertainty and percentage error. It's also relating to density though.
So you're going to need to know density as well as how to deal with errors.
26. This is another one on DC Circuits. And it will come down to setting up some simultaneous equations.
So, to go about that really just write out everything you know,
and see if you can make enough equations out of that, to solve for how many variables you have.
Number 27- we've got an AC Circuit.
And 28- they've given us a few graphs here.
They want us to find the incorrect one.
And it's to do with just looking at them carefully reading the axes and knowing your kinematics.
Nearly at the end. Last page with questions here.
29 we have thermodynamics. And this I believe would be about the first law of thermodynamics.
So, some useful things like that you'll need to get started- knowing what our gamma factor is
and knowing some of these equations here, like the change in internal energy and the temperature.
Number 30 - our last physics question, and this one is about circular motion. So, finding a relation between
a few different variables and seeing what are proportional.
It then goes on to the math section. But, like I said to keep this video from being too long,
I won't go through that in detail.
We can have a little flick through.
It's I guess just as long as the physics section and then we also go on to chemistry.
You can see the diagrams coming in here.
So, that's a little glimpse at what the syllabus is like if you're doing an exam here in India,
if you're doing JEE Mains.
The equations, like that I've written in the margins by no means are all you're going to need to know to solve it.
Some of these are quite involved. Some of them are really tricky.
Yeah, like I said, these were just some of my own notes that I would want to keep in mind,
especially if I was thinking about what I had to memorize and what I needed to get started on some of these
questions. Looking back at some of the stuff, I'm grateful that I've finished my physics degree.
And so I don't have to stress about taking these exams anymore. I'm just looking at them for fun now.
I know that it can be extremely stressful if you're not in my shoes, and you're actually you know,
really stressed about having to perform well on something like this.
So, all I can really say is good luck to you.
I hope that throughout studying you managed to stay healthy and happy as well.
And see that at the end of the exam there is a reward, and there is I guess light at the end the tunnel.
It's really an opportunity to try and show what you know.
Sometimes you won't do as well as you hope to, but I hope that for you other opportunities come up,
maybe after the exams, and that you do end up doing something you really enjoy.
Thank you for watching this.
I hope you learned something or that maybe it was helpful. And I'll see you next time!