Question 1

When you blow some air above the upper face of a paper strip, the paper rises. This occurs because

Accepted Answer

A)  the air above the upper face of the paper moves faster, which makes the pressure higher than at the lower face. 
B)  the air above the upper face of the paper moves faster, which makes the pressure lower than at the lower face. 
C)  the air above the upper face of the paper moves faster but the pressure remains constant. 
D)  the air above the upper face of the paper moves slower, which makes the pressure higher than at the lower face. 
E)  the air above the upper face of the paper moves slower, which makes the pressure lower than at the lower face.

Question 2

Water flows through a pipe having a varying width. More water flows per second through the wide section than through the narrow section because there is more room for it to flow.

Accepted Answer

A)  True 
B)  False

Question 3

A certain coin has a diameter of 21.21 mm, a thickness of 1.95 mm, and weighs 0.04905 N. What is its density?

Accepted Answer

A)  29.1 × 103 kg/m3 
B)  7.26 × 103 kg/m3 
C)  9.25 × 103 kg/m3 
D)  2.31 × 103 kg/m3 
E)  71.2 × 103 kg/m3

Question 4

A sample of tendon 3.00 cm long and 4.00 mm in diameter is found to break under a minimum force of 128 N. If instead the sample had been 1.50 cm long and of uniform composition and cross-sectional area, what minimum force would have been required to break it?

Accepted Answer

A)  32 N 
B)  64 N 
C)  128 N 
D)  256 N 
E)  512 N

Question 5

A copper sphere has a radius of 2.50 m under normal room pressure of 1.0 × 10⁵N/m². If we increase the pressure on this sphere to 10 times the normal room pressure, what is the change in its volume? The bulk modulus for copper is 1.4 × 10¹¹ Pa.

Accepted Answer

The answer of A copper sphere has a radius of...

Question 6

Water, of density 1000 kg/m3, is flowing in a drainage channel of rectangular cross-section. The width of the channel is 15 m, the depth of the water is 8.0 m and the speed of the flow is 2.5 m/s. At what rate is water flowing in this channel?

Accepted Answer

A)  2.0 × 105 kg/s 
B)  2.0 × 103 kg/s 
C)  3.0 × 105 kg/s 
D)  3.0 × 103 kg/s 
E)  3.0 × 102 kg/s

Question 7

One of the dangers of tornados and hurricanes is the rapid drop in air pressure that is associated with such storms. Assume that the air pressure inside of a sealed house is 1.02 atm when a hurricane hits. The hurricane rapidly decreases the external air pressure to 0.910 atm. A square window in an outside wall of the house measures 2.02 m on each side. What net force (directed outwards) is exerted on this window? (1 atm = 1.01 × 105 Pa.)

Accepted Answer

A)  4.53 × 104 N 
B)  5.14 × 104 N 
C)  4.78 × 105 N 
D)  5.37 × 105 N

Question 8

When the pressure applied to an unknown liquid is increased from 1.0 × 10⁷ N/m² to 5.5 × 10⁷ N/m², the volume of the liquid decreases by 0.70%. Calculate the bulk modulus of the liquid.

Accepted Answer

The answer of When the pressure applied to an unknown...

Question 9

A wooden raft has a mass of 50 kg. When empty it floats in water (density  with 69% of its volume submerged. What mass of sand can be put on the raft without it sinking?

Accepted Answer

The answer of A wooden raft has a mass of...

Question 10

In the figure, an open tank contains a layer of oil floating on top of a layer of water (of density 1000 kg/m³) that is 3.0 m thick, as shown. What must be the thickness of the oil layer if the gauge pressure at the bottom of the tank is to be The density of the oil is 510 kg/ .

Accepted Answer

The answer of In the figure, an open tank contains...

Question 11

Salt water is more dense than fresh water. A ship floats in both fresh water and salt water. Compared to the fresh water, the volume of salt water displaced by the ship is

Accepted Answer

A)  greater than the volume of fresh water. 
B)  less than the volume of fresh water. 
C)  the same as the volume of fresh water.

Question 12

A 1000-kg object hangs from the lower end of a steel rod 5.0 m long that is suspended vertically. The diameter of the rod is 0.80 cm and Young's modulus for the rod is 210,000 MN/m2. What is the elongation of the rod due to this object?

Accepted Answer

A)  1.2 cm 
B)  0.46 cm 
C)  0.12 cm 
D)  1.8 cm 
E)  0.047 cm

Exam 14: Fluids and Elasticity

When you blow some air above the upper face of a paper strip, the paper rises. This occurs because

Water flows through a pipe having a varying width. More water flows per second through the wide section than through the narrow section because there is more room for it to flow.

A certain coin has a diameter of 21.21 mm, a thickness of 1.95 mm, and weighs 0.04905 N. What is its density?

A sample of tendon 3.00 cm long and 4.00 mm in diameter is found to break under a minimum force of 128 N. If instead the sample had been 1.50 cm long and of uniform composition and cross-sectional area, what minimum force would have been required to break it?

A copper sphere has a radius of 2.50 m under normal room pressure of 1.0 × 10⁵N/m². If we increase the pressure on this sphere to 10 times the normal room pressure, what is the change in its volume? The bulk modulus for copper is 1.4 × 10¹¹ Pa.

Water, of density 1000 kg/m³, is flowing in a drainage channel of rectangular cross-section. The width of the channel is 15 m, the depth of the water is 8.0 m and the speed of the flow is 2.5 m/s. At what rate is water flowing in this channel?

When the pressure applied to an unknown liquid is increased from 1.0 × 10⁷ N/m² to 5.5 × 10⁷ N/m², the volume of the liquid decreases by 0.70%. Calculate the bulk modulus of the liquid.

A wooden raft has a mass of 50 kg. When empty it floats in water (density with 69% of its volume submerged. What mass of sand can be put on the raft without it sinking?

In the figure, an open tank contains a layer of oil floating on top of a layer of water (of density 1000 kg/m³) that is 3.0 m thick, as shown. What must be the thickness of the oil layer if the gauge pressure at the bottom of the tank is to be The density of the oil is 510 kg/ .

Salt water is more dense than fresh water. A ship floats in both fresh water and salt water. Compared to the fresh water, the volume of salt water displaced by the ship is

A 1000-kg object hangs from the lower end of a steel rod 5.0 m long that is suspended vertically. The diameter of the rod is 0.80 cm and Young's modulus for the rod is 210,000 MN/m². What is the elongation of the rod due to this object?

Exam 14: Fluids and Elasticity

When you blow some air above the upper face of a paper strip, the paper rises. This occurs because

Water flows through a pipe having a varying width. More water flows per second through the wide section than through the narrow section because there is more room for it to flow.

A certain coin has a diameter of 21.21 mm, a thickness of 1.95 mm, and weighs 0.04905 N. What is its density?

A sample of tendon 3.00 cm long and 4.00 mm in diameter is found to break under a minimum force of 128 N. If instead the sample had been 1.50 cm long and of uniform composition and cross-sectional area, what minimum force would have been required to break it?

A copper sphere has a radius of 2.50 m under normal room pressure of 1.0 × 105 N/m2. If we increase the pressure on this sphere to 10 times the normal room pressure, what is the change in its volume? The bulk modulus for copper is 1.4 × 1011 Pa.

Water, of density 1000 kg/m3, is flowing in a drainage channel of rectangular cross-section. The width of the channel is 15 m, the depth of the water is 8.0 m and the speed of the flow is 2.5 m/s. At what rate is water flowing in this channel?

When the pressure applied to an unknown liquid is increased from 1.0 × 107 N/m2 to 5.5 × 107 N/m2, the volume of the liquid decreases by 0.70%. Calculate the bulk modulus of the liquid.

A wooden raft has a mass of 50 kg. When empty it floats in water (density with 69% of its volume submerged. What mass of sand can be put on the raft without it sinking?

In the figure, an open tank contains a layer of oil floating on top of a layer of water (of density 1000 kg/m3) that is 3.0 m thick, as shown. What must be the thickness of the oil layer if the gauge pressure at the bottom of the tank is to be The density of the oil is 510 kg/ .

Salt water is more dense than fresh water. A ship floats in both fresh water and salt water. Compared to the fresh water, the volume of salt water displaced by the ship is

A 1000-kg object hangs from the lower end of a steel rod 5.0 m long that is suspended vertically. The diameter of the rod is 0.80 cm and Young's modulus for the rod is 210,000 MN/m2. What is the elongation of the rod due to this object?

A copper sphere has a radius of 2.50 m under normal room pressure of 1.0 × 10⁵N/m². If we increase the pressure on this sphere to 10 times the normal room pressure, what is the change in its volume? The bulk modulus for copper is 1.4 × 10¹¹ Pa.

Water, of density 1000 kg/m³, is flowing in a drainage channel of rectangular cross-section. The width of the channel is 15 m, the depth of the water is 8.0 m and the speed of the flow is 2.5 m/s. At what rate is water flowing in this channel?

When the pressure applied to an unknown liquid is increased from 1.0 × 10⁷ N/m² to 5.5 × 10⁷ N/m², the volume of the liquid decreases by 0.70%. Calculate the bulk modulus of the liquid.

In the figure, an open tank contains a layer of oil floating on top of a layer of water (of density 1000 kg/m³) that is 3.0 m thick, as shown. What must be the thickness of the oil layer if the gauge pressure at the bottom of the tank is to be The density of the oil is 510 kg/ .

A 1000-kg object hangs from the lower end of a steel rod 5.0 m long that is suspended vertically. The diameter of the rod is 0.80 cm and Young's modulus for the rod is 210,000 MN/m². What is the elongation of the rod due to this object?