Free GED Science Physical Science Practice Test

Question 1

What is the SI unit of force?

Accepted Answer

Newton

Answer

The SI unit of force is the Newton (N), named after Isaac Newton. 1 Newton = 1 kg·m/s².

Question 2

Which of Newton's Laws states that an object in motion stays in motion unless acted upon by an external force?

Accepted Answer

Newton's First Law (Inertia)

Answer

Newton's First Law of Motion states that an object at rest stays at rest, and an object in motion stays in motion, unless acted upon by a net external force — this is the law of inertia.

Question 3

What happens to the temperature of water when it boils at 100°C and becomes steam?

Accepted Answer

The temperature stays constant during the phase change

Answer

During a phase change (like boiling), energy is used to break intermolecular bonds rather than increase temperature. The temperature remains constant at 100°C until all the water has turned to steam.

Question 4

What is the formula for calculating work?

Accepted Answer

W = F × d

Answer

Work = Force × distance (W = Fd). Work is measured in Joules (J).

Question 5

Which of the following is a chemical change (not a physical change)?

Accepted Answer

Wood burning

Answer

Burning wood is a chemical change — it produces new substances (ash, CO₂, water vapor) through a chemical reaction. The other options are physical changes.

GED Practice Test

GED Practice Test

Free GED Science Physical Science Practice Test