AFCT General Science: Physical and Chemical 3

Question 1

What is the difference between speed and velocity?

Accepted Answer

Speed is a scalar quantity (magnitude only); velocity is a vector quantity (magnitude and direction)

Answer

Speed is faster than velocity

Answer

Velocity only applies to objects in space

Answer

There is no meaningful difference

Question 2

What happens during an exothermic chemical reaction?

Accepted Answer

Energy is released to the surroundings, usually as heat

Answer

Energy is absorbed from the surroundings

Answer

No energy change occurs

Answer

Energy is converted entirely to light

Question 3

What is the relationship between wavelength and frequency of electromagnetic waves?

Accepted Answer

They are inversely proportional; as wavelength increases, frequency decreases

Answer

They are directly proportional; as one increases, so does the other

Answer

They are unrelated properties

Answer

Both remain constant for all electromagnetic waves

Question 4

What are the three states of matter and what distinguishes them?

Accepted Answer

Solid, liquid, gas — distinguished by particle arrangement, motion, and energy

Answer

Hot, warm, cold — distinguished by temperature

Answer

Positive, negative, neutral — distinguished by electrical charge

Answer

Light, medium, heavy — distinguished by mass

Question 5

What is an isotope?

Accepted Answer

An atom with the same number of protons but a different number of neutrons

Answer

An atom with a different number of protons than normal

Answer

A negatively charged atom

Answer

A molecule made of two different elements

Question 6

What is Ohm's Law and how does it apply to electrical circuits?

Accepted Answer

Voltage equals current multiplied by resistance (V = IR)

Answer

Resistance equals voltage times current

Answer

Power equals voltage divided by current

Answer

Current increases as resistance increases