Physics 12020 Spring, 2017 UCONN-Stamford 13 Feb 2017 Quiz 4. Take Home (Due Wed
ID: 1559892 • Letter: P
Question
Physics 12020 Spring, 2017 UCONN-Stamford 13 Feb 2017 Quiz 4. Take Home (Due Wed 15-Feb-2017 20 (B) (C) 20, t20: 400. 50 In all three figures above, the resistors represent light bulbs each with resistance of 20 n. (1) What is the equivalent resistance of (A) above? (2pt) (2) What is the equivalent resistance of (B) above? (2 p) (3) If the resistors in (B) are connected to a 9v source, what is the current through the two resistors in parallel? 2pt) 0.3 A through the Aellel lesstips (4) The amount of light produced by a light-bulb will increase with increasing current. is attached to the two ends A 24v battery light output. (2 pt) arrangement (C) making a complete Rank the resistors by increasing 24 OHA /4.4 12A-T 0.49A:1, id the power used in R4 arrangement ctied to a24v battery). czp) 24 30,HIA)(20.oyt (DArsExplanation / Answer
here,
1)
for A)
the equivalent resistance , Req = R/2 = 20/2 = 10 ohm
2)
for B)
the equivalent resistance , Rb = R/2 + R = 30 ohm
3)
current through the circuit , I = 9 /Rb = 0.3 A
as the two parallel resistor are equal
the current is divided equally across them
the current through each parallel resistor , I' = I/2 = 0.15 A
4)
as the resistances are equal
the maximum current passes through R1
and then among R2
and
the minimum current passes through R3 and R4
so the correct order for brightness
R1 > R2 > ( R3 = R4)