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15 Points Two straight conducting rails form a right angle.  A conducting bar in contact with the rails starts at the vertex at t = 0 and moves with a constant velocity v = 5.2 m/s along them.  A magnetic field with B = 0.35 T is directed out of the page.  Calculate: the flux through the triangle formed by the rail at t = 3.0 s the emf around the triangle at that time. The direction of the current flow (Clockwise / Counterclockwise)

10 Points In the following RC circuit, the total resistance is 20k and the battery’s emf is 12 V. Suppose the time constant of this RC circuit is 18 μs. Find:(a) The capacitance of the circuit.(b) The time it takes the voltage across the resistor to reach 9 V after closing the switch.

15 Points If the value of Resistor R1 = 0.75 Ω, determine the current in each branch of the circuit

15 Points In the diagram, the bar AC has a mass of 50 g.  It slides freely on the metal strips 40 cm apart at the edges of the incline.  A current I flows through these strips and the bar, as indicated.  There is a magnetic field By = 0.20 T directed in the -y direction.  How large must I be if the rod is to remain motionless.  (Neglect the slight overhang of the rod)  

The modular arithmetic/remainder of 29 mod 4 is          .

In cryptography, the key take-home message of the birthday phenomenon is to         when collisions matter.

If we assume that the encryption of ‘PLAINTEXT’ with a Caesar cipher is ‘WSHPUALEA’, what key is used in the encryption?

Which of the following is/are a weakness in the Caesar cipher? (Select all that apply.)

Assume there is a six-face dice and all the outcomes are equally likely. When one tosses this dice once, the probability of getting either 1, 3 or 5 is ________.

The LCM (least common multiple) of 16 and 20 is        .