Gravitational constant G dimensions: MCQ with Answer and Explanation

Gravitational constant G dimensions:
A. [M⁻¹L³T⁻²]
B. [ML³T⁻²]
C. [M⁰L⁰T⁰]
D. [M⁻¹L²T⁻²]
Answer: Option A
Solution (By JKExamLibrary)
F = Gm₁m₂/r² ⇒ G = Fr²/(m₁m₂) = [MLT⁻²][L²]/[M²] = [M⁻¹L³T⁻²]. Memory aid: 'G dimensions: [M⁻¹L³T⁻²]; small value reflects weak gravity'. Dimensional analysis frequently tested in competitive exams.

This question belongs to: Science Physics

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Physics Questions

Question #1 Report Error
A hydrometer is used to measure
A. Humidity
B. Wind speed
C. Density of liquids
D. Atmospheric pressure

Correct Answer: Option C


Explanation:
Hydrometer measures relative density (specific gravity) of liquids based on floatation principle. Deeper sinking indicates less dense liquid. Hygrometer measures humidity, anemometer wind speed, barometer pressure.

This question belongs to: Science Physics
Question #2 Report Error
In the photoelectric effect, increasing the intensity of the incident light (while keeping frequency constant) will cause:
A. A change in the threshold frequency of the metal surface.
B. A decrease in the maximum kinetic energy of the emitted electrons.
C. An increase in the number of emitted photoelectrons per second.
D. An increase in the maximum kinetic energy of the emitted electrons.

Correct Answer: Option C


Explanation:
According to Einstein's photoelectric equation, the kinetic energy of emitted electrons depends exclusively on the frequency of the incident light and the metal's work function. Intensity represents the number of photons striking the surface per second. More photons mean more collisions with electrons, leading strictly to an increase in the number of emitted photoelectrons (photoelectric current), not their energy.

This question belongs to: Science Physics
Question #3 Report Error
Convex lens forms virtual image when object is:
A. Within focal length
B. Beyond 2F
C. At 2F
D. Between F and 2F

Correct Answer: Option A


Explanation:
Convex lens: object within focal length (u < f) produces virtual, erect, magnified image (magnifying glass). Beyond F: real images. Memory tip: 'Convex lens: u < f ⇒ virtual image; u > f ⇒ real image'. Ray optics concept frequently tested in competitive exams to verify lens image formation rules.

This question belongs to: Science Physics