NEET 2023 Phase 2 · PhysicsSurface gPrevious Year Question
If R is the radius of the earth and g the acceleration due to gravity on its surface, the mean density of the earth is:
Answer: (A) 3g/(4πRG). Correct Answer (A): 3g/(4πRG) Solution: g = GM/R² with M = ρ(4/3)πR³ ⇒ g = (4/3)πGRρ ⇒ ρ = 3g/(4πGR).
- A.3g/(4πRG)✓
- B.4πgR/(3G)
- C.12πg/(RG)
- D.4πgG/(3R)
Correct Answer
(A) 3g/(4πRG)
Solution & Explanation
Correct Answer (A): 3g/(4πRG) Solution: g = GM/R² with M = ρ(4/3)πR³ ⇒ g = (4/3)πGRρ ⇒ ρ = 3g/(4πGR).
🎯
43,000+ questions in हिंदी & English · one-tap toggle
Open →📚Practice all NEET Physics PYQs chapter-wise →💡Don't get it? Learn the Gravitation concepts →Practice NEET 2023 Phase 2 Physics — free, with instant solutions
43,000+ NEET questions solved step-by-step, chapter-wise, in the MedicNEET app.
More NEET PYQ solutions
PhysThe mass of a planet is 1/10th that of the earth and its diameter is half that of the earth. The acceleration due to gravity on that planet is:PhysA mass falls from height h and its fall-time t is measured in units of the period T of a simple pendulum. On earth t = 2T. The setup is taken to another planet of half the earth's mass and the same radius, giving times t' and T'. Then:PhysIf the mass of the Sun were ten times smaller and the universal gravitational constant G ten times larger, which statement is NOT correct?PhysAn electric dipole with dipole moment 5 × 10⁻⁶ C·m is aligned with the direction of a uniform electric field of magnitude 4 × 10⁵ N/C. The dipole is then rotated through an angle of 60° with respect to the electric field. The change in the potential energy of the dipole is:PhysTwo identical charged conducting spheres A and B have their centres separated by a certain distance. Charge on each sphere is q and the force of repulsion between them is F. A third identical uncharged conducting sphere is brought in contact with sphere A first and then with B and finally removed from both. New force of repulsion between spheres A and B (radii negligible vs separation, treated as point charges) is best given as:PhysThe plates of a parallel plate capacitor are separated by d. Two slabs of different dielectric constant K1 and K2 with thickness 3d/8 and d/2 respectively are inserted in the capacitor. Due to this, the capacitance becomes two times larger than when there is nothing between the plates. If K1/K2 = 1.25, the value of K1 is:PhysA sphere of radius R is carved out of a uniform solid sphere of radius 2R (internally tangent, so its centre is at distance R from the big centre). The ratio of the moment of inertia of the small sphere to that of the remaining part, both about the Y-axis through the big sphere's centre, is:PhysThe Sun rotates once in 27 days. If it expanded to twice its present radius (uniform-density sphere, no external influence), its new period would be about: