Q6. A hollow spherical shell at outer radius R floats just submerged under the water surface. The inner radius of the shell is r . If the specific gravity of the shell material is 278 with respect to water, the value of r is: (1) 98 R (2) 49 R (3) 32 R (4) 13 R
What This Question Tests
The question requires applying Archimedes' principle to a floating hollow sphere, equating its weight to the buoyant force, and using the given specific gravity to find the inner radius.
Concepts Tested
Formulas Used
F_B = ρ_fluid V_submerged g
Mass = Density × Volume
📚 NCERT Sections This Tests
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
9.5 — A Small Bulb Is Placed At The Bottom Of A Tank Containing Water To A
Physics Class 12 · Chapter 9
9.5 A small bulb is placed at the bottom of a tank containing water to a depth of 80cm. What is the area of the surface of water through which light from the bulb can emerge out? Refractive index of water is 1.33. (Consider the bulb to be a point source.)
9.3 — A Tank Is Filled With Water To A Height Of 12.5 Cm. The Apparent
Physics Class 12 · Chapter 9
9.3 A tank is filled with water to a height of 12.5 cm. The apparent depth of a needle lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water? If water is replaced by a liquid of refractive index 1.63 up to the same height, by what distance would the microscope have to be moved to focus on the needle again?
📋 Question Details
- Chapter
- Properties of Matter
- Topic
- Buoyancy and Archimedes' Principle
- Year
- 2020
- Shift
- 05 Sep Shift 1
- Q Number
- Q6
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 10: Mechanical Properties of Fluids
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