Recent content by CalinDeZwart

What is the sign? Is it something I have to add to *2pi x path difference / lambda* (am I on the right track with my formula?) I understand the concepts of reflection and refraction, but I am bad at equations and reasoning. The question itself is also really confusing, am I just measuring the...

Okay cool. So my understanding so far is that light goes from air to glass (n 1.0 to n 1.5 - resulting in a phase change), then back from glass to air (n 1.5 to n 1.0 - no phase change because index is lower?), then same again for the lens? If I need to take into account the index, how do I...

Thanks for your reply, Can you please clarify what you mean? Is it something to do with the light reflecting off the glass and the lens before being reaching the scope?

Homework Statement In a Newton's rings apparatus, find the phase difference (in radians) when an air wedge of 500nm thickness is illuminated with red light (lambda = 640nm). t = 500nm lambda = 640nm radians = degrees × pi / 180° Answer) 13 Homework Equations 2pi x path difference / lambda...

Thanks for your reply. I am good with a) and b), but still struggling with c). My lecturer says I need the diffraction equation from b) and to work out the inverse sine function. I understand what he is saying, but the question seems strangely worded. (c) Calculate the angles at which the...

Homework Statement Consider ultrasound with a frequency of 40 kHz. (a) What is the wavelength and period of a 40 kHz sound wave? (b) The slit width required to give the first order diffraction minimum at thirty degrees. (c) Calculate the angles at which the first three minimums should be...

I worked it out I think. 2.4 = (2x/Vt) - (2x/Vl) 2.4 = (2x/3.2) - (2x/6.2) 1.2 = (x/3.2) - (x/6.2) (1.2)(3.2)(6.2) = (6.2x) - (3.2x) 23.808 = 3.0x x = 23.808/3.0 x = 7.936km x = [7.9km] Thanks for your help.

The best I could come up with t = (d*2) / v d = (t/2) * v However, the question doesn't provide data for t and d is the answer I need to arrive at (7.9) What am I missing?

Thanks for your reply, Unfortunately I cannot get my head around how to tackle this question. I know it is basic math, but it just won't click.

Homework Statement When a workman strikes a steel pipeline with a hammer, he generates both longitudinal and transverse waves. The two types of reflected waves return 2.4 s apart. How far away is the reflection point? (For steel, vL = 6.2 km/s, vT = 3.2 km/s). Homework Equations Unknown...