TALLER SOBRE CORRIENTE Y RESISTENCIA (CAP 27 LIBRO GUÍA)
Los problemas pueden resolverlos en grupos de hasta 3 estudiantes como máximo.
1. A rod of 2.0-m length and a square (2.0 mm 2.0 mm) cross section is made of a material with a
resistivity of 6.0 10
–8
m. If a potential difference of 0.50 V is placed across the ends of the rod, at
what rate is heat generated in the rod?
a. 3.0 W
b. 5.3 W
c. 8.3 W
d. 1.3 W
e. 17 W
2. A light bulb is rated at 30 W when operated at 120 V. How much charge enters (and leaves) the light
bulb in 1.0 min?
a. 17 C
b. 15 C
c. 14 C
d. 13 C
e. 60 C
3. An electric heater is constructed by applying a potential difference of 110 V across a wire with a
resistance of 5.0 . What is the power rating of the heater?
a. 2.0 kW
b. 2.4 kW
c. 1.7 kW
d. 1.5 kW
e. 60 kW
4. What is the resistance of a wire made of a material with a resistivity of
m 1023
8
.
if its length is 2.5
m and its diameter is 0.50 mm?
a. 0.16
b. 0.10
c. 1.28
d. 0.41
e. 0.81
5. Most telephone cables are made of copper wire of either 24 or 26 gauge. If the resistance of 24-gauge
wire is 137 /mile and the resistance of 26-gauge wire is 220 /mile, what is the ratio of the diameter of
24-gauge wire to that of 26-gauge wire?
a. 1.6
b. 1.3
c. 0.62
d. 0.79
e. 0.88
