A3-ft-diameter duct is used to carry ventilating air into a vehicular tunnel at a rate of 9000 ft3/min. tests show that the pressure drop is 1.5 in. of water per 1500 ft of duct. what is the value of the friction factor for this duct and the approximate size of the equivalent roughness of the surface of the duct? ans: f = 0.0292, e = 0.0132ft.

An engine, weighing 3000 n, is supported on a pedestal mount. it has been observed that the engine induces vibration into the surrounding area through its pedestal at the maximum operating speed. determine the stiffness of the dynamic vibration absorber spring in (n/m) that will reduce the vibration when mounted on the pedestal. the magnitude of the exciting force is 250 n, and the amplitude of motion of the auxiliary mass is to be limited to 2 mm note: in this question type-in right numbers, no decimals, no fractions, no unit. approximate to right number if needed

A75mm diameter shaft is supported in a journal bearing 75mm long with a diametral clearance of 0. 1mm. it supports a radial load of 1000 n and is lubricated with sae 50 oil at 70°c. find the friction torque and the power loss when the crankshaft rotates at 2900 rev/min.

Not a characteristic property of ceramic material (a) high temperature stability (b) high mechanical strength (c) low elongation (d) low hardness