Q: Which of the following is the correct formula for Young's modulus $$Y$$?

$$Y = \frac{\text{Tensile stress}}{\text{Tensile strain}} = \frac{F/A}{\Delta l / l_0$}$$

Q: A steel cable with a cross-sectional area of $$2.0 \times 10$$^{-4}$$ \ \text{m}^2$$ supports a load of $$4.0 \times 10^3$ \ \text{N}. $$What is the tensile stress in the cable?

$$8.0 \times 10^7$ \ \text{Pa}$$

Question 1

A uniform beam is supported at both ends and has a heavy object placed exactly at its center. Which of the following statements is true regarding the stresses experienced by the beam?

Accepted Answer

The top of the beam is under compression, and the bottom is under tension.

Question 2

Which of the following is the correct expression for the bulk modulus $$B of a $$material?

Accepted Answer

$$B = -\frac{\Delta p}{\Delta V / V_0$}$$

Question 3

A car is parked on a flat surface. For the car to be in equilibrium, where must its center of gravity be located?

Accepted Answer

Somewhere within the area bounded by the supports (the wheels)

Question 4

A diver is subjected to water pressure from all sides at a depth of 1000 m. What type of stress is the diver experiencing?

Accepted Answer

Bulk stress

Question 5

Which of the following is the correct formula for Young's modulus $$Y$$?

Accepted Answer

$$Y = \frac{	ext{Tensile stress}}{	ext{Tensile strain}} = \frac{F/A}{\Delta l / l_0$}$$

Question 6

A steel cable with a cross-sectional area of $$2.0 	imes 10$$^{-4}$$ \ 	ext{m}^2$$ supports a load of $$4.0 	imes 10^3$ \ 	ext{N}. $$What is the tensile stress in the cable?

Accepted Answer

$$8.0 	imes 10^7$ \ 	ext{Pa}$$

Question 7

A glass rod is stretched until it breaks. The stress at which it breaks is called:

Accepted Answer

Breaking stress

Question 8

Which of the following best describes the condition for rotational equilibrium?

Accepted Answer

The sum of all external torques about any point is zero.

Question 9

A ribbon is being cut by scissors. What type of stress is primarily responsible for the deformation?

Accepted Answer

Shear stress

Question 10

A metal rod of length $$l_0 is $$compressed by a force $$F$$ over a cross-sectional area $$A$$, resulting in a decrease in length $$\Delta l. $$What is the compressive strain?

Accepted Answer

$$\frac{\Delta l}{l_0$}$$

Question 11

Which of the following statements about the center of gravity is correct?

Accepted Answer

It is the point where the net torque due to gravity is zero.

Question 12

A block is subjected to a force parallel to its top surface, causing a displacement $$x$$ while its height is $$h. $$What is the shear strain?

Accepted Answer

$$\frac{x}{h}$$

Question 13

Which of the following best describes elastic hysteresis as seen in a stress-strain curve?

Accepted Answer

The path for increasing stress differs from that for decreasing stress, resulting in energy loss.

Question 14

A human anterior tibial tendon has a Young's modulus of $$1.2 	imes 10^9$ Pa. What does this value represent?

Accepted Answer

The ratio of tensile stress to tensile strain for small deformations.

Question 15

If a body is supported at several points but its center of gravity lies outside the area bounded by the supports, what will happen?

Accepted Answer

The body will tip over.

Question 16

Which of the following is the correct formula for compressibility $$k$$?

Accepted Answer

$$k = \frac{1}{B}$$

Question 17

A steel rod is stretched by a force until it reaches its yield point. What happens if the force is increased further?

Accepted Answer

The rod will undergo plastic deformation and not return to its original length.

Question 18

Which of the following is NOT a correct step in the problem-solving strategy for static equilibrium?

Accepted Answer

Ignore the direction of forces when writing equilibrium equations.

Question 19

A block of volume $$V_0 is $$subjected to an increase in pressure $$\Delta p$$, resulting in a volume change $$\Delta V. $$What is the bulk strain?

Accepted Answer

$$\frac{\Delta V}{V_0$}$$

Question 20

A material has a breaking stress of $$5 	imes 10^8$ Pa. What does this mean in a real-world context?

Accepted Answer

The material can withstand a maximum stress of $$5 	imes 10^8$ Pa before fracturing.

Chapter 11: Equilibrium and Elasticity – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards