335 The Relationship between Voltage, Current & Resistance

Question 1

when circuit resistance or opposition to current is increased, a greater amount of voltage is required to force a given current through the circuit

Question 2

when resistance is decreased, a smaller voltage is required to force a given current through a circuit

Question 3

current in an electrical circuit varies directly with the applied voltage and inversely with the resistance

Question 4

E = I x R

Answer 4

voltage = current x resistance (in ohms)

Question 5

if resistance increases for a given constant voltage the current will decrease

Question 6

if voltage value (E) increases for a given constant resistance the current (I) value will decrease

Question 7

there is a direct relationship between current and voltage when resistance is held constant

Question 8

when using E= I x R to solve for voltage the resistance is also directly proportional to the voltage

Question 9

voltage is directly proportional to current and resistance

Question 10

Power may be defined as the rate at which energy is expended (used up), or the rate at which work is performed when
doing a specified amount of work.

Question 11

Power = Volts (V) x Amperes (I)

Question 12

the ammeter is a device used to measure the current in a circuit

Question 13

the meter is connected in line or what is called in series with the load

Question 14

You need to anticipate the amount of current being measured. Always set the meter to its highest current setting and work
down. If the meter is underrated or under-scale for the circuit current it will cause damage. Warning! In a meter set to read
current, the leads are a direct short.

Question 15

voltmeter

Answer 15

measure the amount of voltage across a source or load

Question 16

Voltmeters measure the voltage across a circuit component. Unlike the ammeter, they can be used without disconnecting
any circuit wires. Meter probes or leads are placed across the circuit component to be measured. This type of circuit connection
is called a parallel connection. When the leads are connected in parallel with the circuit, you are measuring the voltage
difference between the two points.

Question 17

Ohmmeters
Both the ammeter and the voltmeter measure the energized state of the circuit. The ohmmeter , which is designed to
measure resistance, requires that the circuit power be removed or de-energized and the load electrically isolated when
readings are taken.