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37 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Define Density.
What is the equation for density? Give the units of each part. |
The mass per unit volume of a substance. (THE EQUATION CAN BE REARRANGED, JUST LIKE ALL OTHER EQUATIONS IN PHYSICS)
Density unit is kg/m³ Mass unit is kg Volume unit is m³
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What is the equation used to calculate the volume of a sphere? What is the equation used to calculate the volume of a cylinder? |
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1ml = ... cm³ = ... m³ Fill in the blanks. (How many cm³ and m³ is equal to 1 ml?) |
1ml = 1cm³ = (1÷100³)m³ |
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What is an alloy? Why are alloys more favoured than pure metals? |
A compound containing 2 or more metals. Alloys have more desirable properties than pure metals. |
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What two metals does brass consist of? What are the two properties of brass that make it desirable? |
Zinc and copper Resistant to corrosion Resistant to wear. |
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Lets say:
An alloy has volume V and consists of metals A and B.
How would you find the mass of the alloy? |
Alloy mass = mass of A + mass of B.
m = m↓A + m↓B OR (See picture).
Mass of the two metals added together. |
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An alloy has volume V and consists of metals A and B. How would you find the density of the alloy? |
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An alloy has volume V and consists of metals A and B. As a summary, how would you find the: 1) Mass of the alloy 2) Volume of the alloy 3) Density of the alloy? |
1) add the masses of the metals that make up the alloy 2) Volume of the alloy would be given. 3) Density = (added metal masses ÷ given alloy volume) |
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How would you find the volume of an irregular shape solid?
Draw a diagram to support the explanation. |
.Put the irregular solid into a displacement/eureka can filled with water. The volume of water that's forced out is the volume of the irregular object. |
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Lets say for a spring in equilibrium, the weight of the object attached to the spring = mg. What direction is the tension of the spring acting in and what is the tension in the spring? |
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For a system in equilibrium, opposite forces are... |
Equal. |
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What is Hooke's law?
What is the hooke's law equation? State what each part of the equation means. |
The Force applied to a spring is directly proportional to the extension of that spring, as long as the limit of proportionality isnt exceeded.
F = kx k is spring constant (or stiffness) x is extension F is force. |
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What is the symbol for proportionality? |
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Write down the notation that explains hookes law (the notation that shows F is directly proportional to x) |
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This is a spring extending. Label the part that represents the extension. What is the unit that extension is measured in? What are 2 symbols that represent extension? (One of them is x which was covered before. What is the other one?) |
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k is the spring constant of a spring. The value of k represents how stiff a spring is and how hard it would be to extend. If k is Bigger, will the spring be harder to extend or easier to extend? What is the unit of k and why? (Think of the hookes law equation and rearranging for k) |
Bigger k → spring is harder to extend. k unit = N/m since k = F/x from rearranging the hooke's law equation. |
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This is a mass (attached to spring) against extension (of spring) graph. What is the gradient equal to and how can you find k using the gradient? |
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How do you prove that something is directly proportional to something else? E.g. how can you prove that force applied is directly proportional to extension? |
Show that to get the force, the extension must be multiplied by something (spring constant).
( F = kx)
Show that to get one thing, the other thing must be multiplied by something. |
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How do you prove that something is inversely proportional to something else? |
Show that to get one thing, (1 ÷ the other thing) must be multiplied by something. |
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This is a Force against extension graph. What is the gradient equal to? What is the area under the graph equal to? |
Area under the graph = elastic potential energy stored in the spring. |
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What are the 2 equations that can be used to find the elastic potential energy stored in a string (If you aren't given a mass by extension graph OR a force by extension graph to work with)? |
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If 2 springs, both with a spring constant k, are attached in series as shown in the picture, will happen to the extension and how much will it change by? What will happen to the spring constant and how much will it change by? |
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If 2 springs, both with a spring constant k, are attached in parallel as shown in the picture, and one weight is acting on them, what will happen to the extension and how much will it change by? What has happened to the force?What will happen to the spring constant and how much will it change by? |
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Define tensile stress. What is the equation for tensile stress? (Give both the symbol equation and the worded equation. Symbol equation is on hint flashcard) |
Force applied to a wire divided by the cross-sectional area of the wire. |
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Define Tensile Strain. What is the equation for tensile strain? (Give the symbol equation and state the units of each part involved) |
Extension (or change in length) divided by the original length. |
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Define Young's Modulus.
What are the 2 possible units of Young's modulus?
What id the equation for Young's modulus? Give the symbol and word equation. |
Ratio of tensile stress to tensile strain.
Measured in Pa (Pascals) or N/m² Young's modulus = Stress÷Strain. |
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If a wire has a smaller diameter, does it's extension tend to rise or fall? |
Smaller diameter, larger extension. |
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This is an example of a stress-strain graph. What is: P E UTS B?
State what each of the terms mean.
How can you calculate Young's modulus from a graph like this. |
P is limit of proportionality. (The point at which stress is no longer proportional to strain)
E is elastic limit (The point where plastic deformation occurs. In other words, the point of no returning to original length).
UTS is ultimate tensile strength OR ultimate tensile stress (Maximum amount of stress a wire can withstand without breaking. Also seen as the strength of the wire)
B is breaking stress (Stress reauired to break the wire)
B is breaking stress.
To calculate Young's modulus from a graph like this, calculate the gradient of the graph BEFORE it reaches the limit of proportionality (P)
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What does loading mean? What does unloading mean? |
Loading: Applying weights to a wire
Unloading: Removing weights from a wire. |
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On this stress-strain graph, what does the dotted red line represent? |
How the graph will look if load (weights) are removed AFTER reaching the elastic limit (E) |
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Stress-strain graphs may have a yield point (Y) like the graph shown in the picture. What is a yield point? |
A point where after this point, small increases in stress lead to large increases in strain. |
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What is toughness? How can you find the toughness of a wire using a stress strain graph? |
Toughness - A measure of the energy needed to break a material. The area under a stress-strain graph from the origin to the breaking point shows the toughness of thr wire. |
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What does ductile mean? |
When a material is able to undergo a change of form without breaking. |
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These ate the stress-strain graphs of different wires. Which wire is:
The most ductile?
The stiffest?
The strongest?
The toughest?
And why? |
Ductile - A (undergoes a little amount of strain, but has little plastic deformation)
Stiffest - B (No plastic deformation and is a straight line)
Strongest - B (Highest UTS)
Toughest - C (greatest area under curve).
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The stress-strain graph for stretched rubber is unique. Draw what it looks like when it's loaded, then unloaded straight after. What does the area between the two lines represent? |
The area between the two lines is the energy lost per unit volume. |
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When rubber is stretched and released, what is the energy stored in the rubber lost as? What is this process of energy loss called? |
The energy stored in the rubber is lost as heat. This is called hysterisis. |
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This is a force by extension graph. What does the whole area under the black curve represent?
What does the whole area under the dotted red line represent?
What does the area between both the black curve and the red line represent?
Has the thing undergone plastic deformation? If so then explain why. |
Area under Black curve: Energy stored in the spring/wire or whatever the thing is during the loading process.
Area under Red curve: Energy lost by the thing during unloading process.
Area between both: energy left in the thing after all the load has been removed
This thing has undergone plastic deformation because after all the load has been removed, the thing is longer than it was at the start. It can't return back to its original length.
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