Pendulum in accelerating traincar

AI Thread Summary
The discussion revolves around determining the oscillatory period of a pendulum in a constantly accelerating traincar using the small angle approximation. The equations of motion are derived, incorporating gravitational and acceleration forces acting on the pendulum bob. A differential equation is formed, combining the effects of gravity and acceleration. The original poster seeks the most efficient method to solve this differential equation, contemplating the use of Fourier transforms. The conversation emphasizes finding a straightforward solution to the problem.
buttermellow7
Messages
9
Reaction score
0

Homework Statement


A pendulum bob of mass m is suspended by massless thread of length l from the ceiling of a boxcar. The car undergoes constant acceleration a along a straight, level track. What, in the small angle approximation, is the oscillatory period tau of the pendulum?

Homework Equations


F_g=mg\sin\theta=mg\theta
F_a=ma\cos\theta=ma

The Attempt at a Solution


mg\theta+ma=ml\ddot{\theta}
\frac{g}{l} \theta+\frac{a}{l}=\ddot{\theta}

What's the quickest way to solve this differential equation?
 
Physics news on Phys.org
My first idea was to Fourier transform it, but I'm not sure if that would be the best approach. Any suggestions?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top