Answer Happy

[c] For Example 23.1 (Calculating Emf) in Section 23.2 (Faraday's Law of Induction Lenz's Law) of the textbook, replace the radius with X millimeters and time with Y milliseconds (rather than 0.100 s), and then solve the example, showing your work X=4 Y=22.56 [d] For Example 23.2 (Calculating Large Motional Emt) in Section 23.3 (Motional Emf) of the textbook, replace the length of the conductor with X km and the orbital speed with Y hundred meters per second, and then solve the example, showing your work
-- 23.3 63 EXAMPLE 23.1 Calculating Emf: How Great Is the Induced Emf? Calculate the magnitude of the induced emf when the magnet in Figure 23.7(a) is thrust into the coil, given the following information: the single loop coil has a radius of 6.00 cm and the average value of B cos 0 (this is given, since the bar magnet's field is complex) increases from 0.0500 T0 0.250 T in 0.100 s. Strategy To find the magnitude of emf, we use Faraday's law of induction as stated by emf = -NA, but without the minus sign that indicates direction: ΔΦ emf=N- ΔΙ Solution We are given that N = 1 and Ar = 0.100 s, but we must determine the change in flux Ao before we can find emf. Since the area of the loop is fixed, we se@that A0 = A(BA cos 0)= AA(B cos 0). 23.4 Now A(B cos 6)=0.200 T, since it was given that B cos O changes from 0.0500 to 0.250 T. The area of the loop is A = *r? =(3.14..)(0.060 m)2 = 1.13 x 10-2 m². Thus, A0 =(1.13 x 10-2 m?)(0.200 T). Entering the determined values into the expression for emf gives Emf = N 40 (1.13 x 10-2 mº)0.200 T) = 22.6 mV. 0.100 S Discussion While this is an easily measured voltage, it is certainly not large enough for most practical applications. More loops in the coll, a stronger magnet, and faster movement make induction the practical source of voltages that it is 23.5 ΔΙ 23.6
Calculating the Large Motional Emf of an Object in Orbit Tethered Satellite Bearth Return path through ionosphere Figure 23.12 Motional sot as electrical power conversion for the space shuttle is the motivation for the Tethered Satelite experiment. A 5 KV emt was predicted to be induced in the 20 km long tether while moving at orbital speed in the Earth's magnetic field. The circuit is completed by a return path through the stationary ionosphere Calculate the motional emf induced along a 20.0 km long conductor moving at an orbital speed of 7.80 km/s perpendicular to the Earth's 5.00 x 10- Tmagnetic field. Strategy This is a straightforward application of the expression for motional emf-emf = Bev, Solution Entering the given values into emf = Bev gives emf = BV = (5.00 x 10-T)(2.0 x 109 m)(7.80 x 10 m/s) 7.80 x 10' V. 23.10