(14) You purchase an LED with a forward bias voltage of 2V. The manufacturer claims the most efficient current for good brightness and low power loss is 30mA. If using a 5V power supply, what resistance value should you put in series with the diode to achieve the recommended current? (a) 5/30 A (b) 50/3 (c) 500/3 A (d) 150 100 n 30x10 Questions (15) through (16) deal with the circuit shown below. Assume that the diode is ideal (i.e., has a OV forward bias voltage). + V₂- w 1 kQ ++ 1 µF (15) If VA-5V and VB-2V, what is the steady state value for current/? (a) 0 (b) 1/3 mA (c) 1/3000 A (d) 3 mA (e) 3000 A 5-2 (16) If VA-2V and VB-5V, what is the steady state value for current ? (a) 0 (b) -1/3 mA (c) -1/3000 A (d) -3 mA -3000 A Questions (17) through (18) deal with the circuit below. Assume that when the transistor is in saturation, the collector-to-emitter drop is 0.2 V and the base-to-emitter forward bias voltage is 0.7 V. (b) B (e) B (d) AB ③AB (23) What is the value for C in the circuit below? (a) A (c) 0 (d) 1 (24) What is the value for C in the circuit below? (b)A (c) 0 (d) 1 A A+ A A-A Questions (25) through (27) deal with the circuit below A B C B.T (25) D= (a) C-B ⑥C+B (c) C-B (d) C+B A+A =A A-A قد D- E D+E DE F سنا (17) When Vin-0V, Vout- (a) OV (b) 0.2V (c) 0.9V 4.8V (e) 5V (18) When Vin 5V, Vout- (a) OV (b) 0.2V (c) 0.9V (d) 4.8V (c) 5V ΠΩ 5-0.7 4.3 5 (19) The hexadecimal equivalent of the binary number 1000111 is 8F (5) F8 (c) IE (d) El (c) 8E (20) The base ten equivalent of the binary number 10111 is (a) 13 (b) 23 (c) 29 (d) 46 (e) 58 21 +21 +21-23 +241 1+2+4+ (21) The MSB of the binary number 11010 is (b) 0 (c) undefined (22) The Boolean expression A + AB is equivalent to (a) A B 00 1 10 1 AAB 4.Ag (e) B-C (26) I can be written as (a) D E D-E (c)D+E (d) D-E (e) D E (27) If A B C 1. Fis (a) 0 Questions (28) through (29) deal with the truth table below where A and B are inputs and X and Y are outputs A B X Y 0 0 0 יזי 1 0 (28) Using the sum-of-products method, what is the correct expression for Y? (a) B+ AB (b) A+B (c) AB (d) AB+ AB AB+ AB AB+ AB (29) Using the product-of-sums method, what is the correct expression for X? (a) AB ⑩A+B (c)A+B (d)(A+B)(A+B) (e) AB+ AB A+B (30) If the inputs of a positive edge-triggered JK flip-flop are connected with J to ground and K to 5V, at every positive edge of the clock input (CK) the output changes to (or remains at) 0 (b) changes to (or remains at) I (c) toggles (d) uncertain