1.A voltage is described as v(t) = 3u(t) - 3u(t-3) V where u(t) is the step function. The values at t = 2 seconds and t = 4 seconds are x and y respectively, where:
A) x = 3 V and y = -3 V.
B) x = 0 V and y = 3 V.
C) x = 3 V and y = 0 V.
2. A current is described by the function i(t) = 5cos(1000t - 2) mA. The argument of the cosine is in radians and t is in seconds. The frequency may be expressed as:
A) 2 radians/s
B) 1000 Hz
C) 159 Hz
D) 159 radians/s
E) 2 Hz
F) 6280 Hz
3. Consider the signal v(t) = 10cos3000t + 10sin3000t. The peak-to-peak value is:
A) 28.28 V
B) 14.14 V
C) 10 V
D) 20 V
4. A current i(t) = 10r(t) mA is applied to a 10 mF capacitor for t > 0, where r(t) is the ramp function. At t= 0, the capacitor voltage was zero. The voltage across the capacitor at t = 2 s is:
A) 2.0 V
B) 0.5 V
C) 2.5 V
D) 1.5 V
E) 1.0 V
5. The voltage applied to a 100 mF capacitor is v(t) = 10r(t) V. The current through the capacitor at t = 2 s is:
A) 1.0 V
B) 2.0 V
C) 500 mV
D) 5.0 V
E) 200 mV