Recent content by randyrandy

I'm still uneasy because I still don't see a concrete formula(s) connecting energy and radius to amplitude... I'm curious to find out what the formal way of solving this would be using nice neat physics formula.

Thank you for that explanation. formally speaking, what energy equation would be used on the other side of 1/2kx^2 = ? that uses radius in it's equation? why are water waves considered harmonic motion? i thought harmonic meant things like springs and pendulums and stuff?

Would the problem assume that 2cm is the max displacement at 10cm from center? This seemed ambiguous to me. therefore... 1/2k4 = energy (energy would be proportional to circumference pi*2*10cm) at 10cm. at 40cm... 1/2kx^2. what would the energy side of the equation look like at 40cm...

I found this formula for a spring F=kx. Would that be applicable here?

Could you explain how to solve this problem?

1/2kx^2? = energy. but that formula doesn't have radius as a variable.

I'm confused more than ever...

But the answer says it's 1cm not 0.5cm...

maybe circumference? rather than area, just the perimeter of the wave front? so it's pi*2*r? so linear? just intuitively, i know that a ripple will die down as the wave moves from the center...so the amplitude will be smaller...so it'll be inverse relationship to distance. 2*10cm = 1/2cm...

Part of what threw me off was I was uncertain whether the amplitude of 2cm is the peak amplitude for the wave or some height between the maximum amplitude. As to the power equation, I'm not sure. The problem didn't mention anything about power. Oh, wait, energy is conserved so this is really...

I'm stumped. How do you get this without knowing the wavelength? Can someone explain how to get the answer?

The 100W light bulb (cost 0.60 dollars) is not going to be used anymore and is being replaced with the 20W (cost 3 dollars) low energy light bulb. If electricity is charged at $0.15 per kWh, for how many hours must the low energy bulb be used in order for the lower cost of running it to exactly...