I only need question 3 . please show all work . thank you Which of the following
ID: 1630290 • Letter: I
Question
I only need question 3 . please show all work . thank you
Which of the following is (are) correct? A. Like poles of different magnets repel each other. B. Unlike poles of different magnets attract each other. C. For one orientation of a bar magnet, in the plane of this paper, there are four neutral points. (a))AB (b) None of the above (c) ABC (d) C (e) BC. A magnet 20 cm long is aligned so that the nearest neutral point is found, along the longitudinal axis of the magnet, 30 cm from the south pole of the magnet. If the horizontal component of the Earth's magnetic field is 2.5 times 10^-5 Wb/m^2, then what is the strength of each magnetic pole, in Wb? (a) 1.85 times 10^-6 (b) 4.2 times 10^-6 (c) 3.5 times 10^-6 (d) 2.5 times 10^-6 (e) 2.95 times 10^-6. A neutral point is located on the perpendicular bisector to a magnet 40 cm from each pole. The magnet is 20 cm long. The Earth's magnetic field is 2.5 times 10^-5 Wb/m^2. What is the strength of each magnetic pole, in Wb? (a) 3.3 times 10^-5 (b) 1.6 times 10^-5 (c) 1.2 times 10^-5 (d) 4 times 10^-6 (e) 8 times 10^-6. A magnet 20 cm long with a pole strength of 1.95 times 10^-6 Wb is aligned so that neutral points are found on the perpendicular bisector to the magnet. Assuming the strength of the Earth's field to be 2.5 times 10^-5 Wb/m^2, determine the shortest distance, in meters, from a neutral point to the north pole of the magnet. (a) 0.62 (b) 0.25 (c) 0.18 (d) 0.34 (e) 0.50.Explanation / Answer
(3) ans
Given that
earth magnetic field B=2.5*10^-5 Wb/m^2
length L=[40^2+20^2]^1/2=44.71 cm=0.45 m
now we find the strength of the each magnetic pole
the strength of the each magnetic pole B=2.5*10^-5*3.14*0.45^2
=1.6*10^-5 Wb
the correct option is B