The magnetic field is uniform and out of the page inside a circle of radius r, and is essentially zero outside the circular region (see the figure). the magnitude of the magnetic field is changing with time; as a function of time the magnitude of the magnetic field is (b0 + bt3). r1 = 2.4 cm, r2 = 45 cm, b0 = 1.5 t, b = 1.1 t/s3, t = 0.9 s, and r = 16 cm. uploaded image

(b) what is the magnitude of the electric field at location p? (hint: remember that "emf" is the integral of the non-coulomb electric field around a closed path.)
n/c
(d) what is magnitude of the "curly" electric field at location q?
n/c

In a thunderstorm, charge builds up on the water droplets or ice crystals in a cloud. thus, the charge can be considered to be distributed uniformly throughout the cloud. for the purposes of this problem, take the cloud to be a sphere of diameter 1.00 kilometer. the point of this problem is to estimate the maximum amount of charge that this cloud can contain, assuming that the charge builds up until the electric field at the surface of the cloud reaches the value at which the surrounding air breaks down. this breakdown means that the air becomes highly ionized, enabling it to conduct the charge from the cloud to the ground or another nearby cloud. the ionized air will then emit light due to the recombination of the electrons and atoms to form excited molecules that radiate light. in addition, the large current will heat up the air, resulting in its rapid expansion. these two phenomena account for the appearance of lightning and the sound of thunder. take the breakdown electric field of air to be eb=3.00ă—106n/c. part a estimate the total charge q on the cloud when the breakdown of the surrounding air is reached. express your answer numerically, to three significant figures, using ďµ0=8.85ă—10â’12c2/(nâ‹…m2) .

Onsider a u-tube whose arms are open to the atmosphere. now, equal volumes of water (ρ = 62.4 lbm/ft3) and light oil (ρ = 49.3 lbm/ft3) are poured from different arms. a person blows from the oil side of the u-tube until the contact surface of the two fluids moves to the bottom of the u-tube, and thus the liquid levels in the two arms are the same. if the fluid height in each arm is 31 in, determine the gage pressure the person exerts on the oil by blowing. (round the final answer to three decimal places.)

The mass number of fe^2+ is 56. how many neutrons are there in a single fe^2+ atom?