WGU C165 Objective Assessment 2026 | Integrated Physical
Sciences | Practice Questions, Answers & Detailed Explanations -
REAL EXAM LARGE FONT
600 REAL EXAM-STYLE QUESTIONS - LARGE FONT - DIVERSE CONCEPTS - DETAILED
RATIONALES - OA PREP 2026
1. C165 Integrated Physical Sciences - Wave properties - If frequency doubles while
speed stays constant, what happens to wavelength? Variant 4310
A. Wavelength halves because v = f λ, so λ = v/f inversely proportional
B. Wavelength stays same
C. Wavelength doubles
D. Wavelength becomes zero
ANSWER: A
DETAILED EXPLANATION: Wave equation v=fλ. Speed constant medium dependent. Double frequency half
wavelength. - Correct is A. Remember: Wavelength halves because v = f λ, so λ = v/f inversely proportional -
This is a core C165 concept tested on OA.
2. C165 Integrated Physical Sciences - Electromagnetic spectrum order from lowest to
highest energy: Variant 6770
A. Visible < Radio < Gamma < X-ray < UV
B. All EM waves have same energy
C. Gamma < X-ray < UV < Visible < IR < Microwave < Radio
D. Radio < Microwave < Infrared < Visible (red to violet) < Ultraviolet < X-ray < Gamma - energy
increases frequency decreases wavelength
ANSWER: D
DETAILED EXPLANATION: E = h f. Higher frequency = higher energy. Radio longest wavelength lowest
energy, gamma shortest highest. - Correct is D. Remember: Radio < Microwave < Infrared < Visible (red to
violet) < Ultraviolet < X-ray < Gamma - energy increases frequency decreases wavelength - This is a core C165
concept tested on OA.
3. C165 Integrated Physical Sciences - Density of water is 1 g/cm³. A 100 cm³ block of
wood with mass 60 g floats. What percentage is submerged? Variant 5497
A. 0% submerged because wood floats fully above
B. 60% submerged (needs to displace 60 g water = 60 cm³ water, so 60/100 = 60% submerged) -
Archimedes principle
C. 100% submerged because wood absorbs water
D. 40% submerged because 40 g remaining
ANSWER: B
DETAILED EXPLANATION: Float: weight = buoyant force = weight of displaced water. 60g displaces 60 cm³
water, so 60% of block under water. Density 0.6 g/cm³. - Correct is B. Remember: 60% submerged (needs to
displace 60 g water = 60 cm³ water, so 60/100 = 60% submerged) - Archimedes principle - This is a core C165
concept tested on OA.
,4. C165 Integrated Physical Sciences - What causes seasons on Earth? Variant 9148
A. Seasons caused by Earth's rotation
B. Seasons caused by Sun getting hotter in summer
C. Earth closer to Sun in summer
D. Axial tilt 23.5° causes varying solar angle and day length throughout year as Earth orbits Sun,
not distance from Sun
ANSWER: D
DETAILED EXPLANATION: Common misconception: distance not cause. Tilt causes Northern Hemisphere
summer when tilted toward Sun, winter when away. Equinoxes and solstices. - Correct is D. Remember: Axial
tilt 23.5° causes varying solar angle and day length throughout year as Earth orbits Sun, not distance from Sun
- This is a core C165 concept tested on OA.
5. C165 Integrated Physical Sciences - A 5 kg object accelerates at 2 m/s². What is the
net force acting on it according to Newton's Second Law? Variant 4401
A. 7 N because force is mass plus acceleration
B. 2.5 N because force is mass divided by acceleration
C. 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction same as
acceleration.
D. 0 N because constant acceleration means no net force
ANSWER: C
DETAILED EXPLANATION: Newton's Second Law F=ma. 5×2=10 N. Tested: calculate net force, weight = mg.
- Correct is C. Remember: 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction
same as acceleration. - This is a core C165 concept tested on OA.
6. C165 Integrated Physical Sciences - Wave properties - If frequency doubles while
speed stays constant, what happens to wavelength? Variant 7457
A. Wavelength becomes zero
B. Wavelength stays same
C. Wavelength halves because v = f λ, so λ = v/f inversely proportional
D. Wavelength doubles
ANSWER: C
DETAILED EXPLANATION: Wave equation v=fλ. Speed constant medium dependent. Double frequency half
wavelength. - Correct is C. Remember: Wavelength halves because v = f λ, so λ = v/f inversely proportional -
This is a core C165 concept tested on OA.
7. Why is the sky blue and sunset red?
A. Sky blue because reflects ocean
B. Sunset red because Sun cooler at sunset
C. Scattering does not affect color
, D. Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter more by air molecules than
longer (red ~650 nm); at sunset longer path more blue scattered away leaving red
ANSWER: D
DETAILED EXPLANATION: Scattering intensity ~ 1/λ■. Blue scattered ~5x more than red. Explains blue sky
and red sunset. - Correct is D. Remember: Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter
more by air molecules than longer (red ~650 nm); at sunset longer path more blue scattered away leaving red -
This is a core C165 concept tested on OA.
8. C165 Integrated Physical Sciences - Why is the sky blue and sunset red? Variant
1735
A. Sunset red because Sun cooler at sunset
B. Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter more by air molecules than
longer (red ~650 nm); at sunset longer path more blue scattered away leaving red
C. Scattering does not affect color
D. Sky blue because reflects ocean
ANSWER: B
DETAILED EXPLANATION: Scattering intensity ~ 1/λ■. Blue scattered ~5x more than red. Explains blue sky
and red sunset. - Correct is B. Remember: Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter
more by air molecules than longer (red ~650 nm); at sunset longer path more blue scattered away leaving red -
This is a core C165 concept tested on OA.
9. C165 Integrated Physical Sciences - A circuit has 12V battery and 3Ω resistor. What
is current and power dissipated? Variant 6135
A. Current I=V/R=4 A, Power P=VI=48 W or I²R=48 W
B. Current 0.25 A Power 3 W because divide backwards
C. Current 4 A Power 4 W because power equals current
D. Current 36 A Power 432 W because multiply
ANSWER: A
DETAILED EXPLANATION: Ohm's law V=IR, Power P=VI=I²R=V²/R. Core physics calculations for C165. -
Correct is A. Remember: Current I=V/R=4 A, Power P=VI=48 W or I²R=48 W - This is a core C165 concept
tested on OA.
10. C165 Integrated Physical Sciences - A 5 kg object accelerates at 2 m/s². What is the
net force acting on it according to Newton's Second Law? Variant 7180
A. 0 N because constant acceleration means no net force
B. 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction same as
acceleration.
C. 2.5 N because force is mass divided by acceleration
D. 7 N because force is mass plus acceleration
ANSWER: B
DETAILED EXPLANATION: Newton's Second Law F=ma. 5×2=10 N. Tested: calculate net force, weight = mg.
- Correct is B. Remember: 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction
, same as acceleration. - This is a core C165 concept tested on OA.
11. C165 Integrated Physical Sciences - Potential energy vs kinetic energy - a ball at
top of hill 10 m high, mass 2 kg. PE? Variant 3164
A. PE = mgh = 2×9.8×10 = 196 J potential energy converts to kinetic at bottom (ignoring friction)
B. PE = 0 at top
C. PE = 20 J because multiply mass height only
D. PE = 196 J but never converts to kinetic
ANSWER: A
DETAILED EXPLANATION: PE = mgh gravitational potential. Conservation of energy PE+KE constant. At top
PE max, at bottom KE max. - Correct is A. Remember: PE = mgh = 2×9.8×10 = 196 J potential energy converts
to kinetic at bottom (ignoring friction) - This is a core C165 concept tested on OA.
12. C165 Integrated Physical Sciences - A chemical reaction releases heat to
surroundings. Is it endothermic or exothermic, and what happens to entropy of
surroundings? Variant 8707
A. Neutral reaction with no heat change
B. Exothermic - releases heat, surroundings entropy increases, system may decrease, sign ∆H
negative
C. Endothermic because heat is released from system
D. Exothermic but surroundings entropy decreases
ANSWER: B
DETAILED EXPLANATION: Exo = out, endo = in. Exothermic ∆H negative, heat to surroundings increases
disorder of surroundings. - Correct is B. Remember: Exothermic - releases heat, surroundings entropy
increases, system may decrease, sign ∆H negative - This is a core C165 concept tested on OA.
13. C165 Integrated Physical Sciences - What is difference between element,
compound, and mixture? Variant 8818
A. Element one type atom (e.g., O■), compound two+ elements chemically bonded fixed ratio
(e.g., H■O), mixture physically combined variable ratio separable (e.g., salt water)
B. Mixture chemically bonded
C. Compound variable ratio
D. Element and compound same
ANSWER: A
DETAILED EXPLANATION: Matter classification core. Elements periodic table, compounds chemical bonds
covalent ionic, mixtures homogeneous heterogeneous. - Correct is A. Remember: Element one type atom (e.g.,
O■), compound two+ elements chemically bonded fixed ratio (e.g., H■O), mixture physically combined variable
ratio separable (e.g., salt water) - This is a core C165 concept tested on OA.
14. C165 Integrated Physical Sciences - First Law of Thermodynamics - energy cannot
be created or destroyed. Example: Variant 4004
Sciences | Practice Questions, Answers & Detailed Explanations -
REAL EXAM LARGE FONT
600 REAL EXAM-STYLE QUESTIONS - LARGE FONT - DIVERSE CONCEPTS - DETAILED
RATIONALES - OA PREP 2026
1. C165 Integrated Physical Sciences - Wave properties - If frequency doubles while
speed stays constant, what happens to wavelength? Variant 4310
A. Wavelength halves because v = f λ, so λ = v/f inversely proportional
B. Wavelength stays same
C. Wavelength doubles
D. Wavelength becomes zero
ANSWER: A
DETAILED EXPLANATION: Wave equation v=fλ. Speed constant medium dependent. Double frequency half
wavelength. - Correct is A. Remember: Wavelength halves because v = f λ, so λ = v/f inversely proportional -
This is a core C165 concept tested on OA.
2. C165 Integrated Physical Sciences - Electromagnetic spectrum order from lowest to
highest energy: Variant 6770
A. Visible < Radio < Gamma < X-ray < UV
B. All EM waves have same energy
C. Gamma < X-ray < UV < Visible < IR < Microwave < Radio
D. Radio < Microwave < Infrared < Visible (red to violet) < Ultraviolet < X-ray < Gamma - energy
increases frequency decreases wavelength
ANSWER: D
DETAILED EXPLANATION: E = h f. Higher frequency = higher energy. Radio longest wavelength lowest
energy, gamma shortest highest. - Correct is D. Remember: Radio < Microwave < Infrared < Visible (red to
violet) < Ultraviolet < X-ray < Gamma - energy increases frequency decreases wavelength - This is a core C165
concept tested on OA.
3. C165 Integrated Physical Sciences - Density of water is 1 g/cm³. A 100 cm³ block of
wood with mass 60 g floats. What percentage is submerged? Variant 5497
A. 0% submerged because wood floats fully above
B. 60% submerged (needs to displace 60 g water = 60 cm³ water, so 60/100 = 60% submerged) -
Archimedes principle
C. 100% submerged because wood absorbs water
D. 40% submerged because 40 g remaining
ANSWER: B
DETAILED EXPLANATION: Float: weight = buoyant force = weight of displaced water. 60g displaces 60 cm³
water, so 60% of block under water. Density 0.6 g/cm³. - Correct is B. Remember: 60% submerged (needs to
displace 60 g water = 60 cm³ water, so 60/100 = 60% submerged) - Archimedes principle - This is a core C165
concept tested on OA.
,4. C165 Integrated Physical Sciences - What causes seasons on Earth? Variant 9148
A. Seasons caused by Earth's rotation
B. Seasons caused by Sun getting hotter in summer
C. Earth closer to Sun in summer
D. Axial tilt 23.5° causes varying solar angle and day length throughout year as Earth orbits Sun,
not distance from Sun
ANSWER: D
DETAILED EXPLANATION: Common misconception: distance not cause. Tilt causes Northern Hemisphere
summer when tilted toward Sun, winter when away. Equinoxes and solstices. - Correct is D. Remember: Axial
tilt 23.5° causes varying solar angle and day length throughout year as Earth orbits Sun, not distance from Sun
- This is a core C165 concept tested on OA.
5. C165 Integrated Physical Sciences - A 5 kg object accelerates at 2 m/s². What is the
net force acting on it according to Newton's Second Law? Variant 4401
A. 7 N because force is mass plus acceleration
B. 2.5 N because force is mass divided by acceleration
C. 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction same as
acceleration.
D. 0 N because constant acceleration means no net force
ANSWER: C
DETAILED EXPLANATION: Newton's Second Law F=ma. 5×2=10 N. Tested: calculate net force, weight = mg.
- Correct is C. Remember: 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction
same as acceleration. - This is a core C165 concept tested on OA.
6. C165 Integrated Physical Sciences - Wave properties - If frequency doubles while
speed stays constant, what happens to wavelength? Variant 7457
A. Wavelength becomes zero
B. Wavelength stays same
C. Wavelength halves because v = f λ, so λ = v/f inversely proportional
D. Wavelength doubles
ANSWER: C
DETAILED EXPLANATION: Wave equation v=fλ. Speed constant medium dependent. Double frequency half
wavelength. - Correct is C. Remember: Wavelength halves because v = f λ, so λ = v/f inversely proportional -
This is a core C165 concept tested on OA.
7. Why is the sky blue and sunset red?
A. Sky blue because reflects ocean
B. Sunset red because Sun cooler at sunset
C. Scattering does not affect color
, D. Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter more by air molecules than
longer (red ~650 nm); at sunset longer path more blue scattered away leaving red
ANSWER: D
DETAILED EXPLANATION: Scattering intensity ~ 1/λ■. Blue scattered ~5x more than red. Explains blue sky
and red sunset. - Correct is D. Remember: Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter
more by air molecules than longer (red ~650 nm); at sunset longer path more blue scattered away leaving red -
This is a core C165 concept tested on OA.
8. C165 Integrated Physical Sciences - Why is the sky blue and sunset red? Variant
1735
A. Sunset red because Sun cooler at sunset
B. Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter more by air molecules than
longer (red ~650 nm); at sunset longer path more blue scattered away leaving red
C. Scattering does not affect color
D. Sky blue because reflects ocean
ANSWER: B
DETAILED EXPLANATION: Scattering intensity ~ 1/λ■. Blue scattered ~5x more than red. Explains blue sky
and red sunset. - Correct is B. Remember: Rayleigh scattering - shorter wavelengths (blue ~450 nm) scatter
more by air molecules than longer (red ~650 nm); at sunset longer path more blue scattered away leaving red -
This is a core C165 concept tested on OA.
9. C165 Integrated Physical Sciences - A circuit has 12V battery and 3Ω resistor. What
is current and power dissipated? Variant 6135
A. Current I=V/R=4 A, Power P=VI=48 W or I²R=48 W
B. Current 0.25 A Power 3 W because divide backwards
C. Current 4 A Power 4 W because power equals current
D. Current 36 A Power 432 W because multiply
ANSWER: A
DETAILED EXPLANATION: Ohm's law V=IR, Power P=VI=I²R=V²/R. Core physics calculations for C165. -
Correct is A. Remember: Current I=V/R=4 A, Power P=VI=48 W or I²R=48 W - This is a core C165 concept
tested on OA.
10. C165 Integrated Physical Sciences - A 5 kg object accelerates at 2 m/s². What is the
net force acting on it according to Newton's Second Law? Variant 7180
A. 0 N because constant acceleration means no net force
B. 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction same as
acceleration.
C. 2.5 N because force is mass divided by acceleration
D. 7 N because force is mass plus acceleration
ANSWER: B
DETAILED EXPLANATION: Newton's Second Law F=ma. 5×2=10 N. Tested: calculate net force, weight = mg.
- Correct is B. Remember: 10 N (F=ma = 5 kg × 2 m/s² = 10 N). Force is mass times acceleration, direction
, same as acceleration. - This is a core C165 concept tested on OA.
11. C165 Integrated Physical Sciences - Potential energy vs kinetic energy - a ball at
top of hill 10 m high, mass 2 kg. PE? Variant 3164
A. PE = mgh = 2×9.8×10 = 196 J potential energy converts to kinetic at bottom (ignoring friction)
B. PE = 0 at top
C. PE = 20 J because multiply mass height only
D. PE = 196 J but never converts to kinetic
ANSWER: A
DETAILED EXPLANATION: PE = mgh gravitational potential. Conservation of energy PE+KE constant. At top
PE max, at bottom KE max. - Correct is A. Remember: PE = mgh = 2×9.8×10 = 196 J potential energy converts
to kinetic at bottom (ignoring friction) - This is a core C165 concept tested on OA.
12. C165 Integrated Physical Sciences - A chemical reaction releases heat to
surroundings. Is it endothermic or exothermic, and what happens to entropy of
surroundings? Variant 8707
A. Neutral reaction with no heat change
B. Exothermic - releases heat, surroundings entropy increases, system may decrease, sign ∆H
negative
C. Endothermic because heat is released from system
D. Exothermic but surroundings entropy decreases
ANSWER: B
DETAILED EXPLANATION: Exo = out, endo = in. Exothermic ∆H negative, heat to surroundings increases
disorder of surroundings. - Correct is B. Remember: Exothermic - releases heat, surroundings entropy
increases, system may decrease, sign ∆H negative - This is a core C165 concept tested on OA.
13. C165 Integrated Physical Sciences - What is difference between element,
compound, and mixture? Variant 8818
A. Element one type atom (e.g., O■), compound two+ elements chemically bonded fixed ratio
(e.g., H■O), mixture physically combined variable ratio separable (e.g., salt water)
B. Mixture chemically bonded
C. Compound variable ratio
D. Element and compound same
ANSWER: A
DETAILED EXPLANATION: Matter classification core. Elements periodic table, compounds chemical bonds
covalent ionic, mixtures homogeneous heterogeneous. - Correct is A. Remember: Element one type atom (e.g.,
O■), compound two+ elements chemically bonded fixed ratio (e.g., H■O), mixture physically combined variable
ratio separable (e.g., salt water) - This is a core C165 concept tested on OA.
14. C165 Integrated Physical Sciences - First Law of Thermodynamics - energy cannot
be created or destroyed. Example: Variant 4004
