Question

A small toy car draws a 0.50-mA current from a 3.0-V NiCd (nickel-cadmium) battery. In 10 min of operation, (a) how much charge flows through the toy car, and (b) how much energy is lost by the battery? 4. (Resistance and Ohm’s law, Prob. 17.16, 1.0 point) How

Answer 1

Answer:

0.3 Coulomb charge flows through the toy car.

0.9 Joules of energy is lost by the battery

Explanation:

$Current(I)=\frac{charge(Q)}{Time (T)}$

a)

Current drawn from the battery = 0.50 mA = (0.50 × 0.001 A)

milli Ampere = 0.001 Ampere

Duration of time current drawn = T = 10 min = 10 × 60 s = 600 s

1 min = 60 seconds

Charge flows through the toy car be Q

$0.50\times 0.001 A=\frac{Q}{600 s}$

$Q=0.50 \times 0.001 A\times 600 s=0.3 C$

0.3 Coulomb charge flows through the toy car.

b)

$Heat(H)=Voltage(V)\times Current(I)\times Time(T)$

Voltage of the battery = V = 3.0 V

Current drawn from the battery = 0.50 mA = (0.50 × 0.001 A)

Duration of time current drawn = T = 10 min = 10 × 60 s = 600 s

$H=V\times I\time T=3.0 V\times 0.50 \times 0.001 A\times 600 s$

H = 0.9 Joules

0.9 Joules of energy is lost by the battery