Test 1

Question 1

Archimedes’ Principle describes

Answer 1

the buoyant force on an object that is fully or partially submerged in fluid.

Question 2

What are the units of pressure?

Answer 2

atm & Pa

Question 3

In the Magdeburg disks demo done in class, the disks were not possible to pull apart after a vacuum removed the air between the disks because

Answer 3

the atmospheric pressure provides a force from outside the disks that pushes the disks together.

Question 4

An object falls at an angle, fully submerged in a constant-density fluid. The fluid is static and near earth’s surface. Which quantities are needed to calculate the object’s acceleration using Newton’s 2nd Law?

Answer 4

• density of the fluid
• volume of the object
• mass of the object

Question 5

Density is..

Answer 5

the mass of an object divided by volume

Question 6

Consider the Archimedes’ Principle experiment discussed in class in which two objects of the same volume are submerged in water. These objects feel…

Answer 6

the same buoyant force regardless of their masses because they displace the same amount of water.

Question 7

If atmospheric pressure in the evening is 2kPa higher than atmospheric pressure in the morning, the pressure felt by a scuba diver in a pool at a fixed depth is

Answer 7

2kPa higher in the evening compared to morning because the higher atmospheric pressure at the surface increases pressure within the pool.

Question 8

Which of the following would give a correct calculation of the pressure at F?

Answer 8

• F as the deep location and A as the shallow location with h = 5.6 - 3.4m
• E as the deep location and F as the shallow location with h = 3.4m

Question 9

A 1.0-kg object with volume V is submerged halfway in a liquid with density 1500kg/m^3. Which equation would correctly calculate the magnitude of buoyant force if the object is accelerating upwards at 2.0m/s^2?

Answer 9

FB=(9.8 m/s^2)(1500kg/m^3)(1/2*V)