Question

1. Use GRESA Method to solve for
the amount of current that will
flow in a lamp with a resistance
of 40 ohms when the voltage
across the lamp is 15 V.
2. Find the voltage if the re-
sistance is 30 ohms and the cur-
rent is 0.5 amperes.
3. Find the resistance if the cur-
rent is 1.5 amperes and the volt-
age is 15-V.​

Answer 1

Solution:-

[1]

• Resistance ,R = 40 ohms

• Potential Difference,V = 15V

By using Ohm's Law

• V = IR

Substitute the value we get

→ I = V/R

→ I = 15/40

→ I = 0.375 A

Therefore, the current flow in lamp will be 0.375 Ampere.

_______________________________________

[2]

• Resistance ,R = 30 ohms

• Current ,I = 0.5 A

By using Ohm's Law

• V = IR

Substitute the value we get

→ V = 30×0.5

→ V = 15v

Therefore,the voltage is 15 Volts.

_______________________________________

[3]

• Current ,I = 1.5 A

• Potential Difference ,V = 15v

By using Ohm's Law

• V = IR

Substitute the value we get

→ R = V/I

→ R = 15/1.5

→ R = 10 ohms

Therefore, the resistance is 10 ohms.