Question 1

Use the following figure to answer the following question:  
-A steel wire and an aluminum wire of the same length L and diameter d are joined to form a wire of length 2L. The wire is fastened to the ceiling and a mass m is attached to the other end. If the masses of the wires are negligible relative to mass m, the ratio of the stress in the aluminum wire to the stress in the steel wire is

Accepted Answer

A)   less than 1.
B)   equal to 1.
C)   greater than 1.
D)   dependent on mass m.
E)   impossible to determine. B

Question 2

The Young's modulus for aluminum is  . If a 35.0-cm long aluminum bar is shortened by 4.00 mm under a certain load, what is the stress on this bar?

Accepted Answer

A)    .
B)    .
C)    .
D)    .
E)   QUOTE 8.00×109 N/m2. B

Question 3

The bulk modulus of water is 2.00  x 109 N/m2. By how much must the pressure be increased to reduce the volume of 1.00 kg of water from 1.00 to 0.998 L?

Accepted Answer

A)   2.00  x106 N/m2
B)   4.00  x 106 N/m2
C)   2.00  x 107 N/m2
D)   4.00  x 107 N/m2
E)   8.00  x 106 N/m2 B

Question 4

During exercise the volume of a human lung can increase by as much as 15%. If the bulk modulus for a lung is 3.00 kN/m2, what is the change in the pressure?

Accepted Answer

A)   +0.450 Pa
B)   -0.450 Pa
C)   0
D)   -450 Pa
E)   +450 Pa

Question 5

The bulk modulus B has units of

Accepted Answer

A)   force.
B)   energy.
C)   pressure.
D)   mass per unit time.
E)   mass density.

Question 6

Which of the following could not have units of N/m2?

Accepted Answer

A)   Young's modulus
B)   shear modulus
C)   bulk modulus
D)   stress
E)   strain

Question 7

A 4.00 m-long steel cable is used to support a church chandelier. After the 226-kg chandelier is hung from the ceiling, the steel cable is lengthened by 3.00 mm. Calculate the diameter of the cable in millimeters. The Young's modulus for steel is .)

Accepted Answer

A)   1.48
B)   2.17
C)   3.84
D)   4.34E. 6.51

Question 8

A cable lifting a 4.00-lb bowling ball stretches by 3.00 mm. The same cable lifting a 5.00-lb bowling ball stretches by

Accepted Answer

A)   3.05 mm.
B)   3.50 mm.
C)   3.75 mm.
D)   4.00 mm.
E)   4.25 mm.

Question 9

The point that identifies the elastic limit of the material whose graph of stress as a function of strain is shown is

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5

Question 10

An 800-kg mass is hung from a 2.00-m steel wire with a cross-sectional area of 0.250 cm2. Young's modulus for steel is 2.0 *1011 N/m2. How much does the wire stretch?

Accepted Answer

A)   2.56 mm
B)   2.97 mm
C)   3.14 mm
D)   3.86 mm
E)   4.13 mm

Question 11

Young's modulus Y has units of

Accepted Answer

A)   force.
B)   mass density.
C)   energy.
D)   pressure.
E)   mass per unit time.

Question 12

A laboratory experiment on stress-strain shows the following quantitative results:  ,  ,  ,  ,  Which one of the above values represents a possible value for a tensile strain?

Accepted Answer

A)   
B)   
C)   
D)   
E)

Question 13

When pressure changes by value of Δp the change in volume of sphere of side a  is  . If the volume is  , the change in the radius Δr is

Accepted Answer

A)   0.125r.
B)   0.500r.
C)   0.0435r.
D)   0.0646r.
E)   0.250r.

Question 14

Which of the following graphs shows the change in pressure as a function of change in volume for an object with initial volume V?

Accepted Answer

A)   
A)  
B)   
B)  
C)   
C)  
D)   
D)  
E)   
E)

Question 15

A 3.00-m long wire with a diameter of 1.50 mm has Young's modulus of 9.00  x1010 N/m2. What mass has to be attached to the wire so that it would extend it by 3.00 mm under its weight?

Accepted Answer

A)   159 kg
B)   5.16 kg
C)   16.2 kg
D)   64.8 kg
E)   48.6 kg

Question 16

A design project requires you to construct a crane to lift a maximum load of QUOTE 5.00×103kg and with a maximum upward acceleration of 2.00 m/s2. What size diameter steel cable should you use if the cable is to have a safety factor of exactly 5?

Accepted Answer

A)   1.64 cm
B)   1.10 cm
C)   2.68 cm
D)   3.00 cm
E)   1.20 cm

Question 17

The point that identifies the proportional limit of the material whose graph of stress as a function of strain is shown is

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5

Question 18

A 1.00 m-high retaining wall is built out of concrete blocks. Each block weighs 22.2 N and has dimensions of 20.3 cm 9.20 cm 5.60 cm. Estimate the minimum volume stress on a block at the very bottom layer of the wall. Assume that the largest surface areas of blocks are facing each other, the height of the wall cannot exceed 1.00 m, and ignore the thin layer of cement between those faces.

Accepted Answer

A)   2.02104 N/m2 
B)   1.90104 N/m2
C)   2.14104 N/m2
D)   3.45105 N/m2
E)   1.87 N/m2

Question 19

Which of the following statements are correct?

Accepted Answer

A)   You apply tensile stress when you stretch an object along its length.
B)   You apply volume stress when you squeeze an object on all sides.
C)   You apply shear stress when you apply offset forces to deform an object.
D)   All of the above statements are correct.
E)   Only A and B are correct.

Question 20

00x1010 N/m2. Neglect any effect of the temperature difference.)

Accepted Answer

A)   3.35 x 10-5 m3
B)   2.25 x 10-4 m3
C)   1.18 x 10-5 m3
D)   0.15 x 10-4 m3
E)   None of the above.

Exam 9: Elastic Properties of Matter: Stress and Strain

The Young's modulus for aluminum is . If a 35.0-cm long aluminum bar is shortened by 4.00 mm under a certain load, what is the stress on this bar?

The bulk modulus of water is 2.00 x 10⁹ N/m². By how much must the pressure be increased to reduce the volume of 1.00 kg of water from 1.00 to 0.998 L?

During exercise the volume of a human lung can increase by as much as 15%. If the bulk modulus for a lung is 3.00 kN/m², what is the change in the pressure?

The bulk modulus B has units of

Which of the following could not have units of N/m²?

A 4.00 m-long steel cable is used to support a church chandelier. After the 226-kg chandelier is hung from the ceiling, the steel cable is lengthened by 3.00 mm. Calculate the diameter of the cable in millimeters. The Young's modulus for steel is .)

A cable lifting a 4.00-lb bowling ball stretches by 3.00 mm. The same cable lifting a 5.00-lb bowling ball stretches by

The point that identifies the elastic limit of the material whose graph of stress as a function of strain is shown is

An 800-kg mass is hung from a 2.00-m steel wire with a cross-sectional area of 0.250 cm². Young's modulus for steel is 2.0 *10¹¹ N/m². How much does the wire stretch?

Young's modulus Y has units of

A laboratory experiment on stress-strain shows the following quantitative results: , , , , Which one of the above values represents a possible value for a tensile strain?

When pressure changes by value of Δp the change in volume of sphere of side a is . If the volume is , the change in the radius Δr is

Which of the following graphs shows the change in pressure as a function of change in volume for an object with initial volume V?

A 3.00-m long wire with a diameter of 1.50 mm has Young's modulus of 9.00 x10¹⁰ N/m². What mass has to be attached to the wire so that it would extend it by 3.00 mm under its weight?

A design project requires you to construct a crane to lift a maximum load of QUOTE 5.00×103kg and with a maximum upward acceleration of 2.00 m/s². What size diameter steel cable should you use if the cable is to have a safety factor of exactly 5?

The point that identifies the proportional limit of the material whose graph of stress as a function of strain is shown is

Which of the following statements are correct?

00x10¹⁰ N/m². Neglect any effect of the temperature difference.)