Recent content by songoku

No, it is not official answer. It is my own answer. I thought the value of PB and PE will be the same since it is tangent from common point. Same thing for PE and PA so it means that PA = PB = 12 cm. I used the same reasoning for QD and QE and also QE and QC so QD = QC = 12 cm Since PE = 12...

I understand. The correct answer is (B). Thank you very much Lnewqban

Let R = radius of big circle and r = radius of small circle. I worked out that ##R \times r=144## but then not sure how to proceed. I also know AB = CD = 24 cm. Thanks

I understand. Thank you very much for all the help and explanation haruspex, Orodruin, kuruman, Super Man

Maybe you mean something like this? $$mv_Ar_A\sin \theta=mv_Br_B\sin \beta$$ where ##\theta## and ##\beta## is the angle between ##v## and ##r## at point A and B. Using ##v=\omega r##: $$\omega_A r_{A}^{2}\sin \theta=\omega_B r_{B}^{2}\sin \beta$$ The question does not give information about...

Is the radial component of acceleration the centripetal acceleration? Or is it something else? I think it should be angular momentum, so: $$m v_A r_A = m v_B r_B$$ I don't think I can use ##v=\omega r## because it is not circular motion so how to relate the equation to ##\omega##? Sorry, what...

(a) I use centripetal force to solve this question, even though the question states elliptical orbit $$\frac{GMm}{r^2}=m\omega^2 r$$ $$\omega^2 r^3=GM$$ So, $$\omega_{A}^{2} r_{A}^{3}=\omega_{B}^{2} r_{B}^{3}$$ $$\frac{r_A}{r_B}=\left(\frac{\omega_{B}}{\omega_{A}}\right)^{\frac{2}{3}}$$ Is...

I understand I understand the 1st paragraph but sorry I don't understand the 2nd one. How can we know the answer will lie on the line a = b? How can we draw this conclusion from the fact 3a^2 + 2b is strictly increasing in the direction of increasing b, and 3b^2 + 2a is strictly increasing in...

I don't think I understand what the question is asking. Find ##a## and ##b## so that the maximum takes the minimum values? If ##a## and ##b## are real numbers, the maximum values of ##3a^2+2b## and ##3b^2+2a## are infinity. How can infinity take minimum value? I have calculated the values of...

I have checked, it is what I wrote. I understand. I suppose it would be half-cycle average Thank you very much Gordianus, pbuk, Steve4Physics

I know the formula of emf of generator is ##\varepsilon=NBA\omega \sin (\omega t)##. If I draw the graph of emf against time, the graph will be sinusoidal and if I find the average, the average will be zero. How can the average emf of generator is ##\frac{4NBA}{T}##? Thanks

Thank you very much haruspex and Orodruin

Is the answer 1? Because the cord is connected to vibrating source and it vibrates with a frequency of 100 Hz so section A and B have the same frequency Thanks

I understand. Thank you very much for all the help and explanation haruspex, apostolosdt, nasu, Steve4Physics, hutchphd

Is what in my notes incomplete? Because if the intensity increases, I also need to know about the frequency to be able to draw any conclusions about the saturation current. Thanks