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Homework #7: Due Saturday, March 23 by 12 noon
- You have a large number of Zener diodes, each rated for a breakdown voltage of 2.0Volts. You have a power supply that puts out 21.5V. You have a 20Ω resistor that can handle 10 Watts of power running through it. You must power something (draw it as a general resistance 'R') that must have 10.0V across it. (a) Draw the circuit diagram that ensures that 10.0V is across 'R'. (b) Find the maximum power dissipated by the 20Ω power resistor.
- An op amp circuit is shown below. (a) Derive the equation for Vout in terms of the general variables Vin, L1 and R1. (b) If Vin=V0sin(ωt), V0=2.0Volts, L1100μH and R1=10k, find the specific equation for Vout, substituting in all the numbers you can, but with ω and 't' remaining undefined.
- What electric field is required to accelerate an electron from rest to 0.32c within a distance of 18cm? Assume the electric field is uniform.
- An electron has been accelerated to a speed of 0.27c (27% the speed of light). The electron is traveling due north in a region where Earth's magnetic field has a strength of 52,000nT, and points at an angle of 55° below the horizontal. As in class, the horizontal component of the field points due north.
(a) What potential (i.e., voltage) was required to accelerate the electron to this speed? Yes, this is physics-2 electric work-energy.
(b) Find the final equation (numbers, units, unit vectors) for the force on the electron. You must use x for east, y for north and z for straight up from Earth's surface.
(c) By how much does this electron deflect from due north after it has traveled a distance of 20cm northward?
That's all for homework #7.