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What is the definition of density for a material?
What is the definition of density for a material?
Which of these is the correct equation to use to calculate density?
Which of these is the correct equation to use to calculate density?
What is the correct SI unit for density?
What is the correct SI unit for density?
What does the variable 'A' represent in the stress equation?
What does the variable 'A' represent in the stress equation?
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Which of the following is the correct unit for stress?
Which of the following is the correct unit for stress?
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What physical quantity determines the magnitude of the upthrust force an object experiences when submerged in a fluid?
What physical quantity determines the magnitude of the upthrust force an object experiences when submerged in a fluid?
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What is the primary factor that determines if an object will float or sink?
What is the primary factor that determines if an object will float or sink?
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In the strain equation, what does ΔL represent?
In the strain equation, what does ΔL represent?
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Why does a uniform object with a density greater than the liquid it is submerged in always sink?
Why does a uniform object with a density greater than the liquid it is submerged in always sink?
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What is the unit used to express strain?
What is the unit used to express strain?
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What does the Young Modulus of a material indicate?
What does the Young Modulus of a material indicate?
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You have a 2kg block of material which has a volume of 0.1m³. What is the density of the material?
You have a 2kg block of material which has a volume of 0.1m³. What is the density of the material?
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An object is submerged in water, experiencing an upthrust of 10N. According to the text, this means that the weight of the water that is displaced by the object is approximately:
An object is submerged in water, experiencing an upthrust of 10N. According to the text, this means that the weight of the water that is displaced by the object is approximately:
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Which formula is used to calculate the Young Modulus?
Which formula is used to calculate the Young Modulus?
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What is the standard unit for measuring the Young Modulus?
What is the standard unit for measuring the Young Modulus?
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In the context of material properties, what is represented by 'L' when calculating strain?
In the context of material properties, what is represented by 'L' when calculating strain?
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A uniform object submerged in a liquid will sink if:
A uniform object submerged in a liquid will sink if:
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Stokes' Law is applicable to objects of what shape?
Stokes' Law is applicable to objects of what shape?
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For Stokes' Law to be valid, what type of flow is required?
For Stokes' Law to be valid, what type of flow is required?
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What quantity can be calculated using Stokes' Law?
What quantity can be calculated using Stokes' Law?
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In the Stokes' Law equation $F = 6\pi\eta rv$, what does $r$ represent?
In the Stokes' Law equation $F = 6\pi\eta rv$, what does $r$ represent?
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What will be the weight of a submerged object relative to the upthrust, if the object's density is greater than that of the liquid?
What will be the weight of a submerged object relative to the upthrust, if the object's density is greater than that of the liquid?
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If an object sinks in a fluid, what is the relationship between the density of the fluid and the density of the object?
If an object sinks in a fluid, what is the relationship between the density of the fluid and the density of the object?
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What is the defining characteristic of elastic deformation?
What is the defining characteristic of elastic deformation?
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When does an object undergo plastic deformation?
When does an object undergo plastic deformation?
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According to Hooke's Law, what is the relationship between the extension of an elastic object and the force applied?
According to Hooke's Law, what is the relationship between the extension of an elastic object and the force applied?
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What is the significance of the limit of proportionality?
What is the significance of the limit of proportionality?
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What is the elastic limit of a material?
What is the elastic limit of a material?
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What mathematical equation represents Hooke's Law?
What mathematical equation represents Hooke's Law?
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How is mechanical stress defined?
How is mechanical stress defined?
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Which of the following is true for an object that has been deformed past its elastic limit?
Which of the following is true for an object that has been deformed past its elastic limit?
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What is breaking stress?
What is breaking stress?
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What does the yield point signify in materials?
What does the yield point signify in materials?
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What type of energy is stored in a stretched object?
What type of energy is stored in a stretched object?
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Which of the following equations represents the energy stored in a spring?
Which of the following equations represents the energy stored in a spring?
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In a force-extension graph, what does the gradient represent?
In a force-extension graph, what does the gradient represent?
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What does the area under the curve on a force-extension graph represent?
What does the area under the curve on a force-extension graph represent?
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What does the gradient represent on a stress-strain graph?
What does the gradient represent on a stress-strain graph?
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Which equation calculates the energy stored in a spring in terms of force and displacement?
Which equation calculates the energy stored in a spring in terms of force and displacement?
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Study Notes
Density
- Density is defined as mass per unit volume
- The equation for density is: Density = Mass/Volume
- The unit of density is kg/m³
Upthrust
- Upthrust is equal to the weight of the fluid displaced by a submerged object.
Floating and Sinking
- An object floats if the upthrust is greater than or equal to the weight of the object.
- An object sinks if the weight of the object is greater than the upthrust.
Stokes' Law
- Stokes' Law applies to small spherical objects in a fluid with laminar flow.
- The equation for Stokes' Law is: F = 6πηrv
- η is the viscosity of the fluid
- r is the radius of the sphere
- v is the speed of the sphere
Elastic Deformation
- Elastic deformation occurs when an object returns to its original shape after the deforming forces are removed.
Plastic Deformation
- Plastic deformation occurs when an object does not return to its original shape after the deforming forces are removed. It will have permanent deformation.
Hooke's Law
- Hooke's Law states that the extension of an elastic object is directly proportional to the force applied to it, up to its limit of proportionality.
- The equation for Hooke's Law is: F = k∆x
- F is the force applied (N)
- k is the stiffness constant
- ∆x is the extension (m)
Limit of Proportionality
- The limit of proportionality is the point beyond which the force and extension are no longer directly proportional to each other. Hooke's law is no longer obeyed.
Elastic Limit
- The elastic limit is the point beyond which an object will no longer elastically deform and will instead deform plastically.
Mechanical Stress
- Mechanical stress is the force experienced by an object per unit area.
- The equation for stress is: Stress = F/A
- F is the force applied
- A is the cross-sectional area
- The unit of stress is Nm⁻²
Strain
- Strain is a unitless quantity because it's the ratio of two lengths.
- The equation for strain is: Strain = ∆L/L
- ∆L is the change in length
- L is the original length
Young Modulus
- A material's Young Modulus is a measure of how much force is required for a given extension, regardless of the object's dimensions.
- The equation for Young Modulus is Stress/Strain
- The unit of Young Modulus is Nm⁻².
Breaking Stress
- Breaking stress is the maximum stress that an object can withstand before fracturing.
Yield Point
- The yield point is the point beyond which an object will experience a large extension without a substantial increase in the force applied.
Elastic Potential Energy
- Elastic potential energy is the type of energy stored in an object that has been stretched.
Energy Stored in a Spring
- The equations for energy stored in a spring are:
- E = ½F∆x
- E = ½k∆x²
Force-Extension Graph
- The gradient of the linear region represents the elastic constant (k).
- The area under the linear region is equal to the elastic potential energy stored in the spring.
Stress-Strain Graph
- The gradient of the linear region represents the Young Modulus of the material.
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Description
This quiz explores key concepts in physics related to density, upthrust, floating and sinking, and deformation. It covers Stokes' Law and the differences between elastic and plastic deformation. Test your understanding of these fundamental principles.