Free AFCT General Science: Physical and Chemical Questions and Answers 1 — Questions and Answers
Question 1: According to Newton's First Law of Motion, an object in motion will stay in motion unless acted upon by what?
- An equal and opposite reaction
- An unbalanced force (Correct answer)
- Its own inertia
- A constant velocity
Correct answer: An unbalanced force
Newton's First Law, also known as the law of inertia, states that an object's state of motion will not change unless an external, unbalanced force is applied to it. An unbalanced force is required to change the object's velocity (i.e., to accelerate it).
Question 2: The process by which a substance changes directly from a solid to a gas is called what?
- Evaporation
- Condensation
- Sublimation (Correct answer)
- Deposition
Correct answer: Sublimation
Sublimation is the phase transition of a substance directly from the solid to the gas state, without passing through the liquid phase. A common example is solid carbon dioxide (dry ice) turning into gaseous carbon dioxide at room temperature.
Question 3: What form of energy is associated with the motion of an object?
- Potential energy
- Kinetic energy (Correct answer)
- Chemical energy
- Thermal energy
Correct answer: Kinetic energy
Kinetic energy is the energy that an object possesses due to its motion. It is dependent on both the mass of the object and the square of its velocity. Potential energy is stored energy based on an object's position or state.
Question 4: What are the three primary subatomic particles that make up an atom?
- Protons, Neutrons, and Electrons (Correct answer)
- Protons, Neutrinos, and Electrons
- Ions, Neutrons, and Electrons
- Protons, Neutrons, and Isotopes
Correct answer: Protons, Neutrons, and Electrons
An atom is composed of a central nucleus containing positively charged protons and neutral neutrons. Negatively charged electrons orbit this nucleus. These three particles are the fundamental components of an atom.
Question 5: In an electrical circuit, what is the primary function of a resistor?
- Stores electrical charge
- Increases the flow of current
- Measures the voltage
- Impedes the flow of current (Correct answer)
Correct answer: Impedes the flow of current
A resistor is a passive electrical component with a specific electrical resistance. Its primary function is to reduce, or impede, the flow of current. This is useful for controlling current levels, adjusting signal levels, and dividing voltages.
Question 6: A substance with a pH of 2 is considered to be what?
- Acidic (Correct answer)
- Basic
- Neutral
- Saline
Correct answer: Acidic
The pH scale measures how acidic or basic a substance is, ranging from 0 to 14. A pH of 7 is neutral, a pH less than 7 is acidic, and a pH greater than 7 is basic (or alkaline). Therefore, a substance with a pH of 2 is strongly acidic.
Free AFCT General Science: Physical and Chemical Questions and Answers 1
According to Newton's First Law of Motion, an object in motion will stay in motion unless acted upon by what?