Recent content by Jimbob999

Hmm is this in the wrong subforum perhaps?

Homework Statement What range of values of right ascension would be best for viewing stars at a latitude of -32 degrees, 20 arcmins, 10 arcseconds on September 21st? What about an observer at 45deg22arcm11arcs? Homework Equations N/A The Attempt at a Solution On these dates the Sun would be...

Homework Statement The Sun has an absolute visual magnitude of about 4.8 and a particular star has an absolute visual magnitude of –0.29. How many times more luminous is this star than the Sun, assuming these stars have similar spectral types and hence colours? a) 100 times b) 125 times c) 150...

Anyone can help?

Intereference, Interference? But that doesn't really get me anywhere...

Homework Statement A thin film with an index of refraction of 1.60 is placed in one of the beams of a Michelson interferometer. If this causes a shift of 8 bright fringes in the pattern produced by light of wavelength 580 nm, what is the thickness of the film?1.5 µm 2.9 µm 3.9 µm 7.7 µm 16...

I have a feeling this picture tells me all I need? w = 2pi *50 Xc = 15.92 XL = 157.08 Thus Z = 173, thus C. Is that correct reasoning?

Is Jw here the same as the angular frequency wd? The textbook chapter that this refers to says nothing about complex impedance as opposed to regular impedance, so I am not sure I get what you mean?

Homework Statement The impedance of the circuit shown is: A. 41.1 Ω B. 100 Ω C. 173 Ω D. 187 Ω E. 241 Ω Homework Equations Z= sqrt (R^2 + [Xinduct - Xcapac]^2) Wd = 1/sqrt(L * C) Xinduct = WdL Xcapac = 1/WdCThe Attempt at a Solution I think my issues come with the 2nd to 4th...

Thanks qwerty. Was stupidly using circumference instead of radius. Got it now.

Ok, let me show you my working. n is 100 I is 13 A = Pi R^2, which is 506.3. However, I am inclined to take this as one big loop. Thus 45m divided 100 loops. A = 0.159? M = 206.7 or M = 2.07 if take n as 1. So don't think any of my answers are right?

Anyone got any idea?

Oh I couldn't find that equation. But solving for this equation gives me 2.07 x 10^6. I guess I need to convert this to A/m^2, but I am not sure the conversion and couldn't find it on Google anywhere?

Would this be a solenoid and thus use equation B = u0 x i x n ?

Homework Statement A 45-m long wire is coiled so that it makes a coil containing 100 circular loops, one on top of the other. If the wire carries a current of 13 A, what is the magnetic dipole moment of the coil? 21 A·m2 6.7 A·m2 3.3 A·m2 2.6 A·m2 1.2 A·m2 Homework Equations B(z) = u0/2pi...