Jeopardy Transducers (general) Practical Applications of Strain Gauges Properties of Strain Gauges and how they work Stress, Strain, Young’s Modulus Characteristics of Stress-Strain Curves Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400 Q $500 Final Jeopardy

Teams 1: Aaron, Tyran, Darius 2: Alex, Jordan, Tiffany 3: Lia, Wade, Tim

$100 Question from H1 How are transducers classified?

$100 Answer from H1 By the energy that it senses/comes in

$200 Question from H1 Can an energy convertor be a transducer?

$200 Answer from H1 Yes

$300 Question from H1 What is the difference between an analog and digital transducer?

$300 Answer from H1 The analog shows readings on a meter basically and digital shows readings in number form.

$400 Question from H1 Explain why all transducers are not sensors?

$400 Answer from H1 A sensor is something that produces a readable signal output. A sensor is made of transducer(s) BUT transducers can be used and not produce a readable output signal.

$500 Question from H1 What are two properties that differentiate a transducer from an energy convertor?

$500 Answer from H1 Transducers take in only a small amount of energy AND transducers produce an output signal

$100 Question from H2 What is the name of the circuit we used with the strain gauge in one of our labs?

$100 Answer from H2 Wheatstone bridge

$200 Question from H2 Who was the inventor of the strain gauge?

$200 Answer from H2 Arthur Claude Ruge

$300 Question from H2 What are the 6 practical uses for strain gauges?

$300 Answer from H2 Sensing airplane wing deflection, bridge deflection, rail deflection, aerodynamics, auto classification, and dynos

$400 Question from H2 How many sensors does the Tsing Ma Bridge have?

$400 Answer from H2 350 sensors

$500 Question from H2 Where is a dyno connected to?

$500 Answer from H2 A flywheel or crankshaft

$100 Question from H3 What is the formula for stress and strain?

$100 Answer from H3 Stress= F/A Strain= ∆L/L

$200 Question from H3 Who invented the strain gauge?

$200 Answer from H3 Arthur C. Ruge

$300 Question from H3 A strain gauge relies on a change in ___ in order to create a change in voltage which is used to provide a stress reading.

$300 Answer from H3 Resistance

$400 Question from H3 When a material receives a tensile force F it has a stress that corresponds to the applied force. In proportion to the stress the cross-section of the strain gauge wire contracts and the length elongates by ∆L from the length material had before receiving the tensile force. This is a description of what property?

$400 Answer from H3 E: Elastic Modulus (YM Modulus)

$500 Question from H3 Name 3 types of strain gauges.

$500 Answer from H3 1. Foil Strain Gauge 2. Wire Strain Gauge 3. Semi-Conductor Strain Gauge

$100 Question from H4 What is the formula for Young’s Modulus?

$100 Answer from H4 YM= Stress/Strain

$200 Question from H4 Force is to stress as __________ is to strain

$200 Answer from H4 Deformation

$300 Question from H4 What are the two variables needed to calculate Young’s Modulus? What are the two formulas needed to get these variables?

$300 Answer from H4 Stress & Strain. Stress=F/A Strain= L/L

$400 Question from H4 What is the Young’s Modulus equation? Briefly describe what you would use the Young’s Modulus equation for.

$400 Answer from H4 Y.M.=Stress/Stain Can be used to determine the Hardness/Elasticity of a material or object.

$500 Question from H4 A power line is stretched as it strung across two telephone poles. The lines length before stretching is 50 feet after stretching is 60 feet. The diameter of the line is 1 inch. The force being applied to the line under wind is 200 pounds. Calculate the stress AND the strain applied to the line. Then using your stress and strain values, calculate the Y.M value. (Calculate Pi as 3.14)

$500 Answer from H4 Strain=.2 Stress=0.42lb/in 2 Y.M.=2.1 lb/in 2

$100 Question from H5 Name the point where the material involved can no longer return to it’s original shape?

$100 Answer from H5 Elastic Limit

$200 Question from H5 Name the point at which a material can stretch no further?

$200 Answer from H5 Failure Point

$300 Question from H5 Describe the difference between elastic limit and the yield point?

$300 Answer from H5 At the yield point a material begins to “Give Way” to a force, at the elastic limit the material has stretched too far for it to return back to it’s original shape.

$400 Question from H5 A Y.M. graph has a slope of 1/6 At an X(Strain) value of.75 find the Y(Stress) value.

$400 Answer from H5.125

$500 Question from H5 Find the slope of a Y.M graph using the following variables: Stress1=50lb/in 2 Stress2=600lb/in 2 Strain1=.0123 Strain2=.0173

$500 Answer from H5 Slope=550/.005 = lb/in 2

Final Jeopardy What would have a greater Y.M. graph slope. Reinforced concrete Or A bar of aluminum?

Final Jeopardy Answer Reinforced Concrete