52.2k views
5 votes
In a given circuit, the supplied voltage is 1.5 volts. One resistor is 3 ohms and the other is 2 ohms. Use Ohm's law to determine the current in the circuit. 0.3 amps 1.5 amps 7.5 amps 3.3 amps

The purpose of a fuse or circuit breaker is _____. to speed up the current to slow down the current to stop current that is flowing too fast to stop current that is flowing too slow

User Andrew Mao
by
8.6k points

1 Answer

3 votes


Part #1:
You haven't mentioned whether the resistors are in series
or in parallel. It's going to make a difference.

-- If the resistors are in series, then their net effective resistance
is their sum.

(3 ohms) + (2 ohms) = 5 ohms.

Current in the circuit is

(supply voltage) / (total resistance)

= (1.5 volts) / (5 ohms) = 0.3 ampere .


-- If the resistors are in parallel, then their net effective resistance
is
(their product) / (their sum)

= (1 ohms x 2 ohms) / (1 ohm + 2 ohms)

= (2 ohms²) / (3 ohms) = 2/3 ohm .

Current in the circuit is

(supply voltage) / (total resistance)

= (1.5 volts) / (2/3 ohm) = 1.0 ampere .

I guess your resistors are in series, because 0.3 amp
is one of the choices but 1.0 amp isn't.
______________________________________

Part #2.
When it comes to talking about electric current, the terms
"speed up", "slow down", "fast", and "slow" are somewhere
between meaningless and absurd.

The purpose of a fuse or circuit breaker is to shut down a current
that is too great ... too great a magnitude, too many electrons all
trying to crowd their way through the wire at the same time, like
100 lines of ants all carrying bread crumbs through a straw and
back to their hole, when there was only supposed to be one or
two lines.

Speed has nothing to do with it. All electric currents flow through
wires at the same speed, at least in high school. It's a matter of
Amperes, which has nothing to do with speed.
User MartinMoizard
by
7.7k points