Section 1.10: Unit 1 Test (Fluids)

This test assesses your understanding of pressure, density, buoyancy, and fluid dynamics. Attempt all questions without notes or external help.

Part A: Multiple Choice

Which factor does not affect the pressure at a point in a fluid at rest?
a) Depth
b) Fluid density
c) Shape of container
d) Gravitational acceleration
An object floats in water with 60% of its volume submerged. What can you conclude?
a) The object is denser than water
b) The object has the same density as water
c) The object’s density is 60% of water’s density
d) The object’s density is greater than water’s density
Bernoulli’s principle applies most directly to:
a) Static fluids
b) Fluid motion and pressure differences
c) Elastic collisions
d) Nuclear interactions

Explain why the pressure at the bottom of a swimming pool depends only on the depth of water and not on the surface area of the pool.
A block of volume \(0.002 \, \text{m}^3\) floats in water with half its volume submerged. Find the mass of the block.

A horizontal pipe narrows from a diameter of 0.10 m to 0.05 m. If water enters the wide section with speed \(2.0 \, \text{m/s}\), what is its speed in the narrow section?
A cube of side length \(0.20 \, \text{m}\) and density \(600 \, \text{kg/m}^3\) is released into a tank of water. Determine:
a) The buoyant force on the cube.
b) The fraction of the cube’s volume submerged.

MC: 1(c), 2(c), 3(b)
Short Answer: Use \( P = \rho g h \); Mass = density × volume submerged × ρ_water
Problem 6: Apply continuity equation \(A_1 v_1 = A_2 v_2\)
Problem 7: Use Archimedes’ principle, compare buoyant force to weight