Recent content by Nishikino Maki

I understand your tube example, but I don't really see how it applies here. The question says "At that moment", so I assumed that the cars were basically standing still. Is this a wrong assumption?

My book gives the formula Intensity = \frac{Power}{4\pi r^2}. I think you are using energy as power and power as intensity?

Is it? I used the second equation and got power by multiplying intensity and the area the sound wave went over.

The website seems to show up for me. Here is a screenshot

Homework Statement Here is the problem: http://faculty.kfupm.edu.sa/PHYS/kuhaili/doppler_problem.htm {Mentor's edit: Here's the text copied from the url: A fire engine moving to the right at 40 m/s sounds its horn ( frequency 500 Hz ) at the two vehicles shown in the figure. The car is...

The tension force will always be directed along the string, which will always be pointing to the center. Gravity always points downwards. When the object is at the bottom, tension points up and gravity points down. When balancing the forces, T - W = mv^2/r, and T = mv^2/r + W. When the...

I see, I didn't consider the compression/extension as a degree of freedom. Would motion along the x-axis be if the spring (the entire thing, not just one end) was being moved at some velocity along the x-axis? Also, how would it change if the spring had a mass on it? The mass would also need 3...

Thanks for the reply! Your explanations were really helpful. Suppose I have a horizontal spring on a frictionless surface. It can only move in one direction (let's say the x-axis), so does that mean it only has 1 variable? 1 variable and 1 equation would mean 0 degrees of freedom?

Not a textbook/homework problem so I'm not using the format (hopefully that's ok). Can someone offer an explanation of normal modes and how to calculate the degrees of freedom in a system of coupled oscillators? From what I've seen the degrees of freedom seems to be equal to the number of...

That actually makes sense because on a level curve the friction and centripetal forces are the only ones pointing to the center. Then I suppose it would be when the velocity of the car is greater than \sqrt{µgr}?

Homework Statement This isn't a problem from a textbook or homework but just a general question. Say there's a car traveling in a circle and that the track has some coefficient of kinetic friction µ. What would make the car skid? Homework EquationsThe Attempt at a Solution I'm thinking that...

Part of my confusion lies in whether I should be in radians or degrees - the examples in the book all use radians, but when I evaluated the above, I got cos(-790\pi), or 1. Changing the angle to something less than 2\pi still gets me 1. When I use degrees, I get 0.0236, which is closer to...

Homework Statement A simple harmonic wave train of amplitude 3 cm and frequency 200 Hz travels in the +ve direction of x-axis with a velocity of 20 m/s. Calculate the displacement, velocity, and acceleration of a particle situated at 50 cm from the origin at t = 2 s. Homework Equations I used...

Each of the ropes pulling the barge can be thought of as an vector because they have both a magnitude (the tension) and a direction. A vector V of magnitude M and direction \theta above the x-axis can be broken into components: Vx = Mcos(\theta) Vy = Msin(\theta) For part a, the idea is that...

Sorry for bad formatting, I meant \sqrt(1/2) * \sqrt(gh). I decided to do the problem a different way, I used the formula for max height and max range, set max height to half of max range, and solved for the angle. From there I was able to get the max height, which indeed was...