A isolated system in which number of charges present is always constant. Suppose a high energy gamma radiation enters into the isolated system and produces positron and electron (pair production), now the total number of charges present in the system increases right? Then how the charge...
A person in the Earth (stationery frame) observes the clock in the spaceship (which almost moving at the speed of light) runs slow right? and an astronaut in the space-ship observes the clock in the earth, to him the clock also appears slow the same rate as the person observes the clock in the...
What are the purposes of defining the Thermodynamic functions such as H (enthalpy), G (Gibbs function), A (Helmholtz function) in Thermodynamics. I just know the expressions for this functions but unable to understand the physical significance of these functions and also haven't understand what...
The speed of light is constant in all inertial frames of reference
Imagine a thought experiment, an observer at rest sending a light pulse towards a spaceship, he measures the speed of light to be 3x10^8 m/s, now assume that the spaceship also travels at the speed of light and an astronaut in...
While deriving lagrangian equation using D'Alembert's principle, in Goldstien, they defined a variable called "virtual displacement". Why do we need a concept called virtual displacement? What is its signigicance in classical physics?
Consider a plane beam of light is falling normally on a material with thickness (d) and refractive index (n), the light partially transmits and partially reflects the light, so the light transmitting the light travels a distance (2nd) coming out of the material have a phase change of ∏ always...
Homework Statement
I have proved that η does not depend on l, but in the solution the author (classical mechanics by David Morin) claimed that η depends on both of the masses M and m, But i don't understand how, please explain me?
Homework Equations
The Attempt at a Solution
Homework Statement
Solve the below differential equation
Homework Equations
The Attempt at a Solution
I have attached my attempt at solution. But I don't how to get rid of (ln y) term in my equation i.e, i Don't know how to write in terms of y. Please help
I am unable understand this Integral, what does it actually saying? What does that "δ" means here? I haven't learned Calculus of variations, explain me with diagrams with possible.
The expression gives time taken to reach a a distance ds in a medium.
The expression has the dimension of time, But my question is how come the denominator is (c/n)? why it can't be (cn)? explain me.
From Optics by Hecht
He says "only a plane wave of infinite extent will propagate as a plane wave"
What does it mean by " plane of infinite extent" in this context?
Homework Statement
How divergence of r (cap)/ |r|^2 is equal to zero?
Homework Equations
r(cap)= x(cap)+y(cap)+z(cap)
|r|^2 as x^2+y^2+z^2
The Attempt at a Solution
I tried the problem and end up with with a different solution I took r(cap)= x(cap)+y(cap)+z(cap)
|r|^2...
What is the difference between propagation number(K) and wave number(k) described in Optics book written by hecht
He defined K=2π/λ and k=1/λ and both of them have the same units (i.e, meter inverse)
What does wave number of a Harmonic function tells about?
(1) Why differential of work, heat can't be expressed as exact differential function?
(2) How differential of internal energy is an exact differential function and how it is a function of any
two of thermodynamics coordinates?
(1) Exact form of U exists because of the results of experiments in adiabatic work, what are such experiments which gives proof for above statement?
(2) Is differential of Internal energy dU path dependent?
I am physics undergrad and very keen to learn Biophysics. But the problem is I don't know anything about it, I don't know where to start it. Should I need to know much Biology concepts to start learn Biophysics? If yes tell me what are some topics i should know to learn Biophysics.
Why should we bother about Extensive properties in Thermodynamic systems? and
Why do we need specific value of some thermodynamic property? and
what does it tell us about the system? Eg. specific heat capacity?
How density of a thermodynamic system is a intensive property?
Homework Statement
Consider a tube of uniform cross section, let one end (a) of the tube is at height h1 and other end (b) is at height h2, where h2>h. Now an incompressible fluid passing through the tube the workdone to pass the liquid at end (a) P1V1 and workdone to pass the liquid at end...
Homework Statement
Let L be the length of the conductor having uniform cross-section area A and density, let I be the current passing through the conductor. How the total number of positive charge carriers in the conductor of length L is (nAL)?
Homework Statement
problem form div curl grad and all that by h.m.schey
An object moves in xy-plane in such a way that its position vector r is given as a some function of "t" by
r= i acosωt+j bsinωt
show the object moves on the elliptical path
Homework Equations
(x/a)^2+(y/b)^2=1
The...
Homework Statement
let U be a 3x3 matrix containng columns C1, C2, C3. The three column vectors C1= (a,0,0) , C2=(b,d,0), C3=(c,e,f)
prove that if a=0 or d=0 or f=0 (3cases), the columns of U are dependent?
problem from Linear algebra and applications, fourth editon, Gilbert strang...
Homework Statement
This picture is taken from Div, curl, grad and all that by schey, while finding the unit normal vector of the surface S (defined as w=f(x,y)) at a point P, to find the normal vector he considered a two tangent non-collinear vectors (u and v) at a point P, to find u...
If you ask me define Dirac delta function, i can easily define it and prove its properties using laplacian or complex analysis method. But still i don't understand what is the use of DIRAC DELTA FUNCTION in quantum mechanics. As i have done some reading Quantum mechanics from Introduction to...
I am a Final year (3rd year) student studying BSc Physics in India. My undergraduate course is getting completed in one month. As I want to pursue my career in field of physics, I like to do a project especially a theoretical project (kind of writing a junior level thesis) before joining...
Consider a mass M, suspended by a weightless spring (horizontally or vertically). If I apply a force on the mass M, it executes simple harmonic motion. My question is for small displacement (that is pushed or pulled) according to Hooke's law F=-kx, it is equal to force we applied right...
A stone released from balloon moving upwards with some constant velocity, the initial velocity of stone is same as the velocity of balloon with opposite sign, but how? What i thought is that the instant stone is released which goes upwards with balloon, stone which is going upwards would stop...
when a body is slided or move in a horizontal floor, the Frictional force is directly proportional to the Normal force acting on the body. Is there is any proof (emperically or Theoretically)
When a Rigid body is said to be in planar motion, if all all the particles in the Rigid body moves in same plane and these planes are parallel to each other.
I think i misunderstood this definition especially the particles moves in same plane and these planes are parallel to each other...
I studied that Stress is defined as Force per unit area. Force here referred to internal force between the particles in the materials per unit area. am i right?
Is pressure a kind of stress? (Internal force per unit volume) for fluids but i have studied that pressure is external force per...
Suppose a particle of mass M is under gravitational attraction. The Newton's law of gravitation says that F=GMm/r^2, and the part Gm/r^2 is g (acceleration due to gravity how?)
\According to Newton's second law, force is defined as rate of change of momentum or force is defined as product of mass into acceleration, I both of these definitions are same and right.
My questions are,
(1) how can i prove this two definitions are same?
when we say two masses or charges or particles interacts with each other, we have used the word interacts, what does that mean, does that mean a physical contact or something of that kind?
Book: Classical mechanics (textbook) by Douglas Gregory (cambridge publications)
Law of mutual interaction states that when two particle (let it be P1 and P2) interacts, the particle (P1) induces an instantaneous acceleration (a21) on particle P2 and the particle P2 induces an instantaneous...
Newton's laws of motions are not applicable in Non-inertial frames of reference which means only mutually accelerated frames of references, My question is how can we apply Newton's laws of motions for practical experiments such as simple pendulum, motion of a ball, etc. conducted in near surface...