WGU C165 INTEGRATED PHYSICAL SCIENCE: 250+ OA-STYLE
QUESTIONS WITH 100% CORRECT ANSWERS AND DETAILED
EXPLANATIONS
Part 1: Scientific Inquiry & Methodology (Questions 1-30)
1. A student records the rising and setting times of the moon each day for a
month. What type of investigation is this?
A) Controlled experiment
B) Laboratory experiment
C) Observational study
D) Physical model
Answer: C) Observational study
Explanation: An observational study involves observing and recording data
without manipulating variables. The student is simply watching the moon,
not changing anything.
2. A scientist combines two organic substances in a test tube and measures
the amount of product that forms. What type of investigation is this?
A) Field study
B) Natural experiment
C) Observational study
D) Controlled experiment
Answer: D) Controlled experiment
Explanation: In a controlled experiment, the scientist actively manipulates
one variable (mixing chemicals) while keeping other conditions constant to
observe the effect.
3. Which unit of measurement is used for mass in the metric system?
A) Liter
B) Gram
, C) Meter
D) Newton
Answer: B) Gram
Explanation: The gram (and kilogram) is the base metric unit for mass. Liter
measures volume, meter measures length, and newton measures force.
4. A student hypothesizes that "if the temperature of water increases, then
the time it takes for salt to dissolve will decrease." What is the independent
variable?
A) The type of salt
B) The time to dissolve
C) The temperature of water
D) The amount of water
Answer: C) The temperature of water
Explanation: The independent variable is what the scientist changes on
purpose. Here, the student is changing the water temperature to see its
effect.
5. In the same hypothesis (temperature affects dissolving time), what is the
dependent variable?
A) The temperature of water
B) The time to dissolve
C) The container shape
D) The stirring speed
Answer: B) The time to dissolve
Explanation: The dependent variable is what is measured as the outcome.
The dissolving time depends on the temperature change.
6. Which of the following is a controlled variable in an experiment testing how
light color affects plant growth?
A) The color of light
B) The height of the plant
C) The amount of water given daily
D) The growth rate of the plant
, Answer: C) The amount of water given daily
Explanation: A controlled variable is kept constant across all groups. Water
amount must stay the same so that only light color differs.
7. A scientific law describes what happens in nature. Which of the following is
an example of a scientific law?
A) Theory of Evolution
B) Law of Gravity
C) Cell Theory
D) Big Bang Theory
Answer: B) Law of Gravity
Explanation: A law describes a pattern in nature (objects fall toward Earth).
Theories explain why the pattern occurs.
8. A scientific theory explains why a phenomenon occurs. Which statement
about a scientific theory is true?
A) It is just an uneducated guess.
B) It can never be changed.
C) It is supported by a large body of evidence.
D) It becomes a law after enough testing.
Answer: C) It is supported by a large body of evidence.
Explanation: A scientific theory is a well-tested, widely accepted
explanation based on evidence. It can change if new evidence arises, and it
does not become a law.
9. Which of the following is a proper hypothesis?
A) I wonder if salt dissolves faster in hot water.
B) Salt might dissolve faster in hot water because it is a common fact.
C) If the water temperature is higher, then the salt will dissolve faster
because particles move more.
D) Hot water is better for dissolving salt.
Answer: C) If the water temperature is higher, then the salt will dissolve
faster because particles move more.
, Explanation: A proper hypothesis is an if-then statement that includes a
prediction and a reasoning. It is testable and falsifiable.
10.Why is replication important in scientific experiments?
A) To make the experiment more expensive
B) To ensure results are reliable and not due to chance
C) To change the hypothesis
D) To use more equipment
Answer: B) To ensure results are reliable and not due to chance
Explanation: Repeating an experiment multiple times (replication) helps
confirm that the results are consistent and not a one-time accident.
11.Which tool would you use to measure the volume of a liquid precisely?
A) Ruler
B) Balance scale
C) Graduated cylinder
D) Thermometer
Answer: C) Graduated cylinder
Explanation: A graduated cylinder is designed to measure liquid volume
accurately. A ruler measures length, a balance measures mass, and a
thermometer measures temperature.
12.Which unit is used to measure force?
A) Gram
B) Liter
C) Newton
D) Meter per second
Answer: C) Newton
Explanation: The Newton (N) is the SI unit for force. Gram is mass, liter is
volume, and meter per second is speed.
13.A graph shows plant height on the y-axis and days on the x-axis. What type
of relationship is shown if the line goes upward from left to right?
A) Negative correlation
B) Positive correlation
QUESTIONS WITH 100% CORRECT ANSWERS AND DETAILED
EXPLANATIONS
Part 1: Scientific Inquiry & Methodology (Questions 1-30)
1. A student records the rising and setting times of the moon each day for a
month. What type of investigation is this?
A) Controlled experiment
B) Laboratory experiment
C) Observational study
D) Physical model
Answer: C) Observational study
Explanation: An observational study involves observing and recording data
without manipulating variables. The student is simply watching the moon,
not changing anything.
2. A scientist combines two organic substances in a test tube and measures
the amount of product that forms. What type of investigation is this?
A) Field study
B) Natural experiment
C) Observational study
D) Controlled experiment
Answer: D) Controlled experiment
Explanation: In a controlled experiment, the scientist actively manipulates
one variable (mixing chemicals) while keeping other conditions constant to
observe the effect.
3. Which unit of measurement is used for mass in the metric system?
A) Liter
B) Gram
, C) Meter
D) Newton
Answer: B) Gram
Explanation: The gram (and kilogram) is the base metric unit for mass. Liter
measures volume, meter measures length, and newton measures force.
4. A student hypothesizes that "if the temperature of water increases, then
the time it takes for salt to dissolve will decrease." What is the independent
variable?
A) The type of salt
B) The time to dissolve
C) The temperature of water
D) The amount of water
Answer: C) The temperature of water
Explanation: The independent variable is what the scientist changes on
purpose. Here, the student is changing the water temperature to see its
effect.
5. In the same hypothesis (temperature affects dissolving time), what is the
dependent variable?
A) The temperature of water
B) The time to dissolve
C) The container shape
D) The stirring speed
Answer: B) The time to dissolve
Explanation: The dependent variable is what is measured as the outcome.
The dissolving time depends on the temperature change.
6. Which of the following is a controlled variable in an experiment testing how
light color affects plant growth?
A) The color of light
B) The height of the plant
C) The amount of water given daily
D) The growth rate of the plant
, Answer: C) The amount of water given daily
Explanation: A controlled variable is kept constant across all groups. Water
amount must stay the same so that only light color differs.
7. A scientific law describes what happens in nature. Which of the following is
an example of a scientific law?
A) Theory of Evolution
B) Law of Gravity
C) Cell Theory
D) Big Bang Theory
Answer: B) Law of Gravity
Explanation: A law describes a pattern in nature (objects fall toward Earth).
Theories explain why the pattern occurs.
8. A scientific theory explains why a phenomenon occurs. Which statement
about a scientific theory is true?
A) It is just an uneducated guess.
B) It can never be changed.
C) It is supported by a large body of evidence.
D) It becomes a law after enough testing.
Answer: C) It is supported by a large body of evidence.
Explanation: A scientific theory is a well-tested, widely accepted
explanation based on evidence. It can change if new evidence arises, and it
does not become a law.
9. Which of the following is a proper hypothesis?
A) I wonder if salt dissolves faster in hot water.
B) Salt might dissolve faster in hot water because it is a common fact.
C) If the water temperature is higher, then the salt will dissolve faster
because particles move more.
D) Hot water is better for dissolving salt.
Answer: C) If the water temperature is higher, then the salt will dissolve
faster because particles move more.
, Explanation: A proper hypothesis is an if-then statement that includes a
prediction and a reasoning. It is testable and falsifiable.
10.Why is replication important in scientific experiments?
A) To make the experiment more expensive
B) To ensure results are reliable and not due to chance
C) To change the hypothesis
D) To use more equipment
Answer: B) To ensure results are reliable and not due to chance
Explanation: Repeating an experiment multiple times (replication) helps
confirm that the results are consistent and not a one-time accident.
11.Which tool would you use to measure the volume of a liquid precisely?
A) Ruler
B) Balance scale
C) Graduated cylinder
D) Thermometer
Answer: C) Graduated cylinder
Explanation: A graduated cylinder is designed to measure liquid volume
accurately. A ruler measures length, a balance measures mass, and a
thermometer measures temperature.
12.Which unit is used to measure force?
A) Gram
B) Liter
C) Newton
D) Meter per second
Answer: C) Newton
Explanation: The Newton (N) is the SI unit for force. Gram is mass, liter is
volume, and meter per second is speed.
13.A graph shows plant height on the y-axis and days on the x-axis. What type
of relationship is shown if the line goes upward from left to right?
A) Negative correlation
B) Positive correlation
