Question 1

When a heavy barge floats above a fish swimming in the water below, does the PRESSURE exerted upon the fish change (and why)?

Accepted Answer

NO. The barge displaces just e

Question 2

A narrow tube is placed vertically in a pan of water, and the water rises in the tube to 4 cm above the level of the pan. The surface tension in the liquid is lowered to one-half its original value by the addition of some soap. What happens to the height of the liquid column in the tube?

Accepted Answer

A)  It drops or rises, but the height cannot be calculated from the information given. 
B)  It remains at the same height. 
C)  It drops to 2 cm. 
D)  It drops to 1 cm. 
A)  It drops or rises, but the height cannot be calculated from the information given. 
B)  It remains at the same height. 
C)  It drops to 2 cm. 
D)  It drops to 1 cm.

Question 3

Two Styrofoam balls, of radii R and 2R, are released simultaneously from a tall tower. Which will reach the ground first?

Accepted Answer

A)  the larger one 
B)  Both will reach the ground simultaneously. 
C)  the smaller one 
D)  The result will depend on the atmospheric pressure. 
A)  the larger one 
B)  Both will reach the ground simultaneously. 
C)  the smaller one 
D)  The result will depend on the atmospheric pressure.

Question 4

Which has the greatest effect on the flow of fluid through a pipe? That is, if you made a 10% change in each of the quantities below, which would cause the greatest change in the flow rate?

Accepted Answer

A)  the fluid viscosity 
B)  the length of the pipe 
C)  the fluid density 
D)  the radius of the pipe 
E)  the pressure difference 
A)  the fluid viscosity 
B)  the length of the pipe 
C)  the fluid density 
D)  the radius of the pipe 
E)  the pressure difference

Question 5

An object completely submerged in water must either rise or fall.

Accepted Answer

A) True 
 B)False

Question 6

A polar bear of mass 200. kg stands on an ice floe 100. cm thick. What is the minimum area of the floe that will just support the bear in saltwater of specific gravity 1.03? The specific gravity of ice is 0.98.

Accepted Answer

The answer of A polar bear of mass 200. kg...

Question 7

A submarine rests on the sea bottom. The normal force exerted upon the sub by the sea-floor is equal to

Accepted Answer

A)  the weight of the sub plus the weight of the displaced water. 
B)  the weight of the sub. 
C)  the weight of the sub less the weight of the displaced water. 
D)  the weight of the displaced water. 
E)  the buoyant force less 1 atmosphere acting on the sub. 
A)  the weight of the sub plus the weight of the displaced water. 
B)  the weight of the sub. 
C)  the weight of the sub less the weight of the displaced water. 
D)  the weight of the displaced water. 
E)  the buoyant force less 1 atmosphere acting on the sub.

Question 8

Which of the following is not a dimensionless number?

Accepted Answer

A)  specific gravity 
B)  stress 
C)  strain 
D)  Reynolds number 
A)  specific gravity 
B)  stress 
C)  strain 
D)  Reynolds number

Question 9

A circular window of 30.0 cm diameter in a submarine can withstand a maximum force of 1.88 × 106 N. What is the maximum depth to which the submarine can go without damaging the window?

Accepted Answer

A)  1.20 km 
B)  945 m 
C)  1.33 km 
D)  2.70 km 
E)  750 m 
A)  1.20 km 
B)  945 m 
C)  1.33 km 
D)  2.70 km 
E)  750 m

Question 10

Steady flow means that all the particles of a fluid have the same velocity as they pass a given point.

Accepted Answer

A) True 
 B)False

Question 11

When soup gets cold, it often tastes greasy. This "greasy" taste seems to be associated with oil spreading out all over the surface of the soup, instead of staying in little globules. This is readily explained in terms of

Accepted Answer

A)  the decrease in the surface tension of water with increasing temperature. 
B)  the Bernoulli effect. 
C)  the increase in the surface tension of water with increasing temperature. 
D)  Archimedes Principle. 
E)  Poiseuille's law. 
A)  the decrease in the surface tension of water with increasing temperature. 
B)  the Bernoulli effect. 
C)  the increase in the surface tension of water with increasing temperature. 
D)  Archimedes Principle. 
E)  Poiseuille's law.

Question 12

A viscous oil flows through a narrow pipe. If the diameter of the pipe were doubled, the flow rate should increase by what factor?

Accepted Answer

A)  6 
B)  4 
C)  2 
D)  8 
E)  16 
A)  6 
B)  4 
C)  2 
D)  8 
E)  16

Question 13

By how much will mercury rise (or fall) in a 1.0 mm diameter glass tube (contact angle 140.°, Hg density 13.6 g/cc, surface tension 0.45 N/m)?

Accepted Answer

The answer of By how much will mercury rise (or...

Question 14

Atmospheric pressure does NOT correspond to approximately

Accepted Answer

A)  1.0 × 102 N/m2. 
B)  0.1 MPa. 
C)  2.4 × 102 oz/in2. 
D)  2.2 × 103 lb/ft2. 
E)  15. lb/in2. 
A)  1.0 × 102 N/m2. 
B)  0.1 MPa. 
C)  2.4 × 102 oz/in2. 
D)  2.2 × 103 lb/ft2. 
E)  15. lb/in2.

Question 15

Suppose that an 80. kg person walking on crutches supports all his weight on the two crutch tips, each of which is circular with a diameter of 1.0 inch. What pressure is exerted on the floor? Express the answer in psi.

Accepted Answer

A)  14. psi 
B)  1.4 × 102 psi 
C)  1.1 × 102 psi 
D)  56 psi 
E)  2.2 × 102 psi 
A)  14. psi 
B)  1.4 × 102 psi 
C)  1.1 × 102 psi 
D)  56 psi 
E)  2.2 × 102 psi

Exam 9: Solids and Fluids

When a heavy barge floats above a fish swimming in the water below, does the PRESSURE exerted upon the fish change (and why)?

A narrow tube is placed vertically in a pan of water, and the water rises in the tube to 4 cm above the level of the pan. The surface tension in the liquid is lowered to one-half its original value by the addition of some soap. What happens to the height of the liquid column in the tube?

Two Styrofoam balls, of radii R and 2R, are released simultaneously from a tall tower. Which will reach the ground first?

Which has the greatest effect on the flow of fluid through a pipe? That is, if you made a 10% change in each of the quantities below, which would cause the greatest change in the flow rate?

An object completely submerged in water must either rise or fall.

A polar bear of mass 200. kg stands on an ice floe 100. cm thick. What is the minimum area of the floe that will just support the bear in saltwater of specific gravity 1.03? The specific gravity of ice is 0.98.

A submarine rests on the sea bottom. The normal force exerted upon the sub by the sea-floor is equal to

Which of the following is not a dimensionless number?

A circular window of 30.0 cm diameter in a submarine can withstand a maximum force of 1.88 × 106 N. What is the maximum depth to which the submarine can go without damaging the window?

Steady flow means that all the particles of a fluid have the same velocity as they pass a given point.

When soup gets cold, it often tastes greasy. This "greasy" taste seems to be associated with oil spreading out all over the surface of the soup, instead of staying in little globules. This is readily explained in terms of

A viscous oil flows through a narrow pipe. If the diameter of the pipe were doubled, the flow rate should increase by what factor?

By how much will mercury rise (or fall) in a 1.0 mm diameter glass tube (contact angle 140.°, Hg density 13.6 g/cc, surface tension 0.45 N/m)?

Atmospheric pressure does NOT correspond to approximately

Suppose that an 80. kg person walking on crutches supports all his weight on the two crutch tips, each of which is circular with a diameter of 1.0 inch. What pressure is exerted on the floor? Express the answer in psi.

Measurement and Problem Solving

Kinematics: Description of Motion

Motion in Two Dimensions

Force and Motion

Work and Energy

Linear Momentum and Collisions

Circular Motion and Gravitation

Rotational Motion and Equilibrium

Temperature and Kinetic Theory

Heat

Thermodynamics

Vibrations and Waves

Sound

Electric Charge, Forces, and Fields

Electric Potential, Energy, and Capacitance

Electric Current and Resistance

Basic Electric Circuits

Magnetism

Electromagnetic Induction and Waves

AC Circuits

Reflection and Refraction of Light

Mirrors and Lenses

Physical Optics: The Wave Nature of Light

Vision and Optical Instruments

Relativity

Quantum Physics

Quantum Mechanics and Atomic Physics

The Nucleus

Nuclear Reactions and Elementary Particles

Filters

A circular window of 30.0 cm diameter in a submarine can withstand a maximum force of 1.88 × 10⁶ N. What is the maximum depth to which the submarine can go without damaging the window?