Physics Practice: Physical Quantities and Measurement (Mock Test 4 - Expert)
1. Expert Analysis: An object weighs $W$ in air and $W_1$ in a liquid of density $\rho_l$. The volume of the object is calculated as:
2. Clinical Logic: Why does a person float more easily in the Dead Sea compared to a normal swimming pool?
3. Data Interpretation: If the R.D. of a substance is $x$ and it is weighed in a liquid of R.D. $y$ ($x > y$), the apparent loss in weight is:
4. Experimental Setup: When measuring the density of a liquid using a density bottle, which error is most likely if the bottle is not wiped dry from outside?
5. A hydrometer works on the principle that the depth of immersion is:
6. If a body of mass $m$ floats in a liquid, the upthrust $F_B$ is:
7. Why do icebergs pose a great danger to ships despite floating?
8. A Plimsoll line on a ship is a mark to ensure:
9. If a solid floats in water with 1/3 of its volume immersed, its R.D. is:
10. Lactometer is a modified hydrometer used specifically to check:
11. A body weighs $W$ in air. When it is fully immersed in a liquid, it weighs $W_{app}$. The R.D. of the body is:
12. Why does a piece of cork stay on the surface of water while a piece of lead sinks?
13. The density of gases is usually expressed in:
14. When water freezes into ice at 0°C, its density:
15. The "Center of Buoyancy" is the center of gravity of the:
16. If a body weighs $20 \text{ N}$ in air and $18 \text{ N}$ in water, what is its volume? ($g = 10 \text{ m/s}^2$)
17. An irregular solid is placed in a Eureka can. The volume of water collected is $40 \text{ ml}$. This represents the solid's:
18. For a body to float, its center of gravity and center of buoyancy must be:
19. Why does a balloon filled with Hydrogen rise, but one filled with Air falls?
20. What is the Relationship between R.D. and Density in CGS?
