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The useful life of a machine bearing depends on its operating temperature, as shown by the following data. Plot the data and obtain a functional description of the data. Estimate a bearing’s life if it operates at 150°F.
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System Dynamics
- 1.22 In order to prevent frostbite to skiers on chair lifts, the weather report at most ski areas gives both an air temperature and the wind-chill temperature. The air temperature is measured with a thermometer that is not affected by the wind. However, the rate of heat loss from the skier increases with wind velocity, and the wind-chill temperature is the temperature that would result in the same rate of heat loss in still air as occurs at the measured air temperature with the existing wind. Suppose that the inner temperature of a 3-mm-thick layer of skin with a thermal conductivity of 0.35 W/m K is and the air temperature is . Under calm ambient conditions the heat transfer coefficient at the outer skin surface is about (see Table 1.4), but in a 40-mph wind it increases to . (a) If frostbite occurs when the skin temperature drops to about , do you advise the skier to wear a face mask? (b) What is the skin temperature drop due to the wind?arrow_forward۱۰:۱۳ docs.google.com * Fixed-Fixed bar was 20 centigrade degree at room temperature, Determine the thermal stress when the bar is heated to :110 degree A Lo Est = 200 Gpa = 11.7 μm/m°C ας ast Ast = 200 mm² _187.2 MPa (compression) +187.2 MPa (compression) 210.6 MPa (compression) 210.6 MPa (Tension) + 210.6 MPa (compression) + 210.6 MPa (Tension) +187.2 MPa (Tension) O non of these _187.2 MPa (Tension) (arrow_forwardCalculate the ankle torque during running pushoff from the following data set to 1 decimal place. NOTE if your answer is negative put the negative sign in the answer! Fz 1720 N Fx 551 N e to search CoP z 0 m Cop x 0.452 m Ankle z 0.143 m Ankle x 0.373 m Answer: Check B B M N Ps 2°C Partly sunnyarrow_forward
- S The following are the values of righting levers, in metres, at various angles of inclination for a ship: KN (m) 450 4.70 (Tonne) 7000 10000 15000 20000 25000 00 60° 150 1,86 1.77 1.68 309 3.87 3.66 3.50 3.41 3.42 750 6.22 6.30 6.32 900 5.92 5.96 5.91 5.70 5.36 0.0 5.35 0.0 5.79 0.0 0.0 0.0 4.95 4.85 4.55 4.18 5.86 5.38 4.76 1.63 1.67 6.14 5.92 In a particular condition of loading the displacement is made up as follows: Item Lightship Cargo Fuel Stores Mass (Tonnes) 6000 5900 1300 Kg (m) 8.17 5.02 3.66 100 10.97 Plot the cross curves of stability and from them, draw the curve of statical stability for the given condition. State the range of stability and the maximum GZ. [Ans: 0-75.5°; 0.46 m]arrow_forwardThe nuchal ligament in a horse supports the weight of the horse’s head. This ligament is much more elastic than a typical ligament, stretching from 15% to 45% longer than its resting length as a horse’s head moves up and down while it runs. This stretch of the ligament stores energy, making locomotion more efficient. Measurements on a segment of ligament show a linear stress-versusstrain relationship until the stress approaches 0.80. Smoothed data for the stretch are shown. The volume of the ligament stays the same as it stretches, so the cross-section area decreases as the length increases. Given this, how would a force F versus change in length ΔL curve appear?arrow_forwardIdentify the equations that go with these concepts: Conservation of Energy (for conservative forces) b. Work-Energy Principle C. Force of gravity for an object near the surface of the Earth Force of gravity for an object far from the surface of the Earth d. T1+ V1 = T2+ V2 T1 + U1->2= T2 F = mg F= (GMm)/r^2arrow_forward
- The surface tension of a fluid is a measure of its resistance to deformation. Select one: True Falsearrow_forward3. Examine your data in Data Table 2 and in Data Table 3. For the data with the smallest percentage difference, compare the total energy at each point. Calculate the sum U₁+Ug at x₁ as ½kx-mgx₁. Calculate that sum at x₂ as ½kx²-mgx₂. Do you expect them to agree reasonably well? Explain why they should or should not be the same. 4. Consider the same data as used in Question 3. Calculate the value of x halfway between x₁ and x₂. Calculate U₁+Ug=½kx² − mgx_for_that point. Do you expect them to agree with the energy calculated in Question 3? If they agree reasonably well, explain why they do. If they do not agree, explain why they do not agree.arrow_forwardQ1. The following data is obtained during geothermal drilling operation. Rock density = 1550 kg/m ³, heat capacity of the rock = 0.00163 J/kg K, temperature difference = 80 K. How much will be the thermal heat content of the rock at the geothermal site? Discuss about geothermal gradients their importance in energy exploration. Do you think utilization of geothermal energy worldwide is increasing yearly? Justify your answer. Do you think the geothermal energy available in this site can be used for a metal melting industry?arrow_forward
- Determine the stability margin for a vehicle with the following parameters; Parameter Value Units Mass 1,870 kg Wheelbase 2.59 Forward weight bias 46 Front axle cornering 67 kN/rad stiffness Rear axle cornering stiffness 67 kN/rad Provide your answer with the units kNm/rad to two decimal places. Your answer must have the correct sign, be it positive or negative (+/-).arrow_forwardbarometric pressure or 1 atmospheric 1 pressure is equal to 1.019 kgf/cm2 O 1 kgf/cm2 O 0.9 kgf/cm2 O 0 kgf/cm2 O * What is the period of vibration of a system that has k=5000 and m=55 kg 0.658 sec 0 sec O 0.557 sec C 0.612 sec The specific volume of a liquid is :the reciprocal of mass density specific volume specific weight O weight density * A pressure gage connected to a tank reads 500 kPa at a location where the atmospheric pressure is 94 kPa. .Determine the absolute pressure in the tank 594 KPa O 550 KPa 600 KPa 602 KPa A Carnot heat engine operates between a source at 1000 K and a sink at 300 K. If the heat engine is supplied with heat at a rate of 800 kJ/min, determine the thermal efficiency 70% 72% 75% 80% OOarrow_forwardThe floor area of the model in the image below is 500 square inches, and the floor area of the house is 1,280 square feet. If the model has a room with a side length of 5 inches, then what is the scale factor for the model to the actual floor? ©2018 AlessandoMassiniano / Getty mages Plus O 5 in:8 ft O 5 in:12 ft O 5 in:36 ft O 5 in:64 ftarrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning