Laws of motion Definition and 25 Discussions

"Reversibility means that we never lose information, that at a fundamental level we can always retrodict the past as well as predict the future in the laws of physics". Susskind in his Theoretical minimum Lecture 2 describes about the laws which are true and which are not. He tells the law of...

Hello to everyone :smile: I'd like to study this problem. You have a 2D guide, described by an equation y = y (x) in a reference interval x ∈ I = [a, b], placed in a cartesian vertical plane Oxy. The guide is frictionless and the only force that is acting is the gravity force. On this track, a...

Quantum mechanics has argued for years that space is not a vacuum. Arguments attempting to brush aside quantum mechanics vacuum theory claiming, it's 'just a quantum mathematical theory' can now put to rest. In this article, laboratory experimentation demonstrates that the Casimir Effect can...

I used work energy theorem between initial top point and point x along the incline(downwards) i got the expression of v then diffrentiated it to get a maxima but it gives me a wrong ans which is 10/6 but the actual ans is 10/3 please tell me what i did wrong

I tried making the fbd of both blocks the block on the incline will have mgsin30 friction force, tension and centrepetal force's cos component similarly second block will have mg tension and friction where normal will be centrepetal force after solving my ans is not matching

At the moment of throwing the ball the ball will have a vertical vel of 4 and horizontal of 3 wrt to elevator so as seen from inside the elevator the ball will behave like a projectile where g(eff) = 8 and with time period 1 sec hence range will be the displacement which should be 3 m but ans...

Homework Statement How to apply constraints in the system to get a relationship between the displacements of block of mass m and pulley of mass M.? Homework Equations ∑T.a= 0 The Attempt at a Solution Assuming tension in both strings to be T . -T × a1 ( for the block) + 2T × a2 ( for the...

Homework Statement [/B] Homework Equations [/B] The Attempt at a Solution In the second question at 5:32,why doesn't the block have a spring force.In FBD of 2nd block it should have been mg-(T+kx)=ma right?

Imagine, There's a ball in deep space traveling with a constant velocity of 25m/s and is having mass 25kg. Now as I said, ball is traveling with a constant velocity that simply means acceleration=0 and now if we calculate the force with F=ma we will end up with 0. But if that ball collide with a...

Homework Statement With the equations of motion in polar coordinates given by ##r(t)=pcos{kt^2}, φ(t)=kt^2## determine the velocity intensity of a point ##M## on the circumference of a cylinder which is rolling without friction on a horizontal plane at time ##t## is the velocity of the center...

Homework Statement 2. The attempt at a solution Let rightward acceleration of the block (A+B) be $$a$$. Let downward acceleration of block (A) be $$a'$$ down. For block A: $$mg-T=ma'$$ $$N+ma=0$$ For block B: $$T+N=Ma$$ On solving $$N=-\dfrac{m^2g}{M+2m}$$ by taking $$a=a'$$.But...

Suppose there is a beaker filled with water placed on a weighing machine. Suppose the reading is x kg. Now, if i immerse a solid block inside the beaker without touching the walls or the bottom of the beaker, will the reading given by the weighing machine increase or not?

Suppose there is a pulley(of negligible mass) and a string(of negligible mass) passes through the groove and two equal masses are attached to each end of the string. Now, if the whole arrangement is attached on a spring balance what will be the reading of the spring balance. Will it be zero?

Homework Statement xg=x*(dv/dt)+v^2 is a differential equation Which has a solution of the form v=at Where a is a constant.Find a Homework Equations dv/dt=v*(dv/dx) V=dx/dt A=dv/dt=d^2x/dt^2 The Attempt at a Solution I assumed 'a' as a function of g That is a=kg for some constant k And...

Homework Statement In order to raise a mass 'm' a man ties it to a rope and passes the rope over a friction less pulley. He climbs the rope with an acceleration 3g/2 relative to the rope. If the mass of the man is m/2 and the mass of the rope is negligible, the tension in the rope is a) 3mg/2...

can a resultant external force on a body change its mass but keep velocity of its centre of mass constant ? Is it practically possible - ##\vec{F}_{ext}=\vec{v}_{com}\frac{\mathrm{d} M}{\mathrm{d} t}## where F is nonzero

Homework Statement Consider a wedge of mass ##m## whose upper surface is a quarter circle and is smooth. The lower part is rough. A small block of same mass is kept at the topmost position and the initial position is shown in figure. The block slides down the wedge. Find the minimum value of...

Homework Statement A block of mass ##M = 1 kg## is placed of a fixed rough incline of inclination ##\theta=sin^{-1} \frac{7}{10}## and coefficient of friction ##\mu=\frac{1}{\sqrt{51}}##. It is connected to a spring of spring constant 100 N/m. Initially the spring is in natural state with...

Homework Statement Find the minimum force ##\displaystyle F## required to move ##\displaystyle M_2##. Details and Assumptions: ##\displaystyle M_1 = 3Kg## ##\displaystyle M_2 = 5Kg## ##\displaystyle \mu_1 = 0.4## ##\displaystyle \mu_2 = 0.6## ##\displaystyle g = 9.8m/s^2## Homework...

Homework Statement A rope of uniform mass per unit length ##\lambda## and length ##L## lies curled on a table, with a short length ##\delta l## of it hanging through a hole in the table. At time zero, the rope begins to slide through the hole. At what time ##t_c## (in seconds) does the end of...

Homework Statement [/B] A sphere of radius $1m$ and mass $25 Kg$ is put on another sphere of radius $5 m$ and $7 Kg$ which is placed on a smooth ground. Now the upper sphere is pushed very slightly from it's equilibrium position and it begins to fall. Now when the line joining the centre of...

Homework Statement Two identical blocks of mass M are tied with a mass-less string of length L. If the string is pulled with a force F right at the midpoint of string L, the blocks will move towards each other. What will the velocity be when the blocks collide. The blocks start from rest and...

Homework Statement Block C is moving with a velocity v0 and block A and B are moving with velocities v1 and v2 with respect to block C. Find the relation between v0, v1 and v2 Homework Equations none The Attempt at a Solution Since the string is in-extensible, its velocity at both ends...

<<Mentor note: Edited for language>> 1. Homework Statement If I have a feather and a hammer and drop it at the same time from the same height (with out air resistance, so basically in a vacuum) Why would it land on the ground at the exact same time? Homework Equations F = ma The Attempt at...

I am a 10th grade student, and I tried for a few weeks now to find a proof to Kepler first and second laws. Is there a simple proof to Kepler' s laws?