When a capacitor is charged, the electric field E, and hence the electric flux Φ, between the plates changes. This change in flux induces a magnetic field, according to Ampère's law as extended by Maxwell: ∮B⃗ ⋅dl⃗ =μ0(I+ϵ0dΦdt). You will calculate this magnetic field in the space between capacitor plates, where the electric flux changes but the conduction current I is zero. A parallel-plate capacitor with circular plates is charged by a constant current I. The radius a of the plates is much larger than the distance d between them, so fringing effects are negligible. Calculate B(r), the magnitude of the magnetic field inside the capacitor as a function of distance from the axis joining the center points of the circular plates. Express your answer in terms of μ0 and given quantities. B(r) =

Under conditions for which the same room temperature is maintained by a heating or cooling system, it is not uncommon for a person to feel chilled in the winter but comfortable in the summer. provide a plausible explanation for this situation (with supporting calculations) by considering a room whose air temperature is maintained at 20â°c throughout the year, while the walls of the room are nominally at 27â°c and 14â°c in the summer and winter, respectively. the exposed surface of a person in the room may be assumed to be at a temperature of 32â°c throughout the year and to have an emissivity of 0.90. the coefficient associated with heat transfer by natural convection between the person and the room air is approximately 2 w/m2 â‹…â‹… k. what is the ratio of the thermal resistance due to convection to the thermal resistance due to radiation in the summer? what is the ratio of thermal resistances in the winter

First, launch the video below. you will be asked to use your knowledge of physics to predict the outcome of an experiment. then, close the video window and answer the question at right. you can watch the video again at any point. part a as in the video, we apply a charge +q to the half-shell that carries the electroscope. this time, we also apply a charge –q to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? view available hint(s) as in the video, we apply a charge + to the half-shell that carries the electroscope. this time, we also apply a charge – to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? it deflects more than it did at the end of the video. it deflects the same amount as at end of the video. it does not deflect at all. it deflects less than it did at the end of the video. submit

What is the final velocity of the initial velocity of 25 and -50?