EmSAT Physics 2

Question 1

What is the potential energy of a 5 kg object at a height of 10 meters? (g = 10 m/s²)

Accepted Answer

500 J

Answer

Gravitational potential energy = mgh = 5 kg × 10 m/s² × 10 m = 500 J.

Question 2

Which law of thermodynamics states that energy cannot be created or destroyed?

Accepted Answer

First Law

Answer

The First Law of Thermodynamics (Law of Conservation of Energy) states that energy cannot be created or destroyed, only transformed from one form to another.

Question 3

What happens to the current in a circuit if the resistance is tripled and voltage remains constant?

Accepted Answer

Current is reduced to one-third

Answer

By Ohm's Law (V = IR), if V is constant and R triples, then I = V/R becomes V/(3R), which is one-third of the original current.

Question 4

What is the net force on an object moving at constant velocity?

Accepted Answer

Zero

Answer

According to Newton's First Law, an object moving at constant velocity has zero net force acting on it — all forces are balanced.

Question 5

What is the focal length of a converging lens if an object at 30 cm produces an image at 15 cm?

Accepted Answer

10 cm

Answer

Using the thin lens equation: 1/f = 1/v + 1/u = 1/15 + 1/30 = 2/30 + 1/30 = 3/30 = 1/10, so f = 10 cm.

EmSAT Practice Test

EmSAT Practice Test

EmSAT Physics 2