EmSAT EmSAT Physics 3

Question 1

What is Ohm's Law?

Accepted Answer

V = IR

Answer

Ohm's Law states that voltage (V) equals current (I) times resistance (R): V = IR. It describes the relationship between these three electrical quantities.

Question 2

What is the SI unit of electrical resistance?

Accepted Answer

Ohm

Answer

The SI unit of electrical resistance is the Ohm (Ω), named after Georg Simon Ohm. It measures how much a component opposes current flow.

Question 3

In a series circuit, how does current behave?

Accepted Answer

It is the same throughout

Answer

In a series circuit, current is the same at all points. There is only one path for current to flow, so the same current passes through all components.

Question 4

What happens to total resistance when resistors are connected in parallel?

Accepted Answer

Total resistance decreases

Answer

In parallel circuits, total resistance decreases because adding more paths gives current more ways to flow. The total resistance is less than the smallest individual resistor.

Question 5

Calculate the power dissipated by a 10 Ω resistor with 2 A flowing through it.

Accepted Answer

40 W

Answer

Power = I²R = (2)² × 10 = 4 × 10 = 40 W. Alternatively, V = IR = 20 V, then P = VI = 20 × 2 = 40 W.

EmSAT Practice Test

EmSAT Practice Test

EmSAT EmSAT Physics 3