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Air enters the intake scoops S at the rate of 50 m3/s. If the engine burns fuel at the rate of 0.4 kg/s and the gas (air and fuel) is exhausted relative to the plane with a speed of 450 m/s, determine the resultant drag force exerted on the plane by air resistance. Assume that air has a constant density of 1.22 kg/m3. Hint: Since mass both enters and exits the plane, Eqs.15-28 and 15-29 must be combined to yield
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Engineering Mechanics: Dynamics (14th Edition)
- While cruising in level flight at a speed of 600 mi/h, a jet plane scoops in air at the rate of 200 lb/s and discharges it with a velocity of 2100 ft/s relative to the airplane. Determine the total drag due to air friction on the airplane.arrow_forwardThe jet is traveling at a speed of 500 mi/h, 30degrees with the horizontal If the fuel is being spent at 4 lb/s , and the engine takes in air at 410 lb/s , whereas the exhaust gas (air and fuel) has a relative speed of 32700 ft/s , determine the acceleration of the plane at this instant. The drag resistance of the air is FD=(0.7v2)lb, where the speed is measured in ft/s. The jet has a weight of 15000 lbarrow_forwardA7.1-Mg truck is resting on the deck of a barge which displaces 398 Mg and is at rest in still water. If the truck starts and drives toward the bow at a speed relative to the barge Vrel = 4.4 km/h, calculate the speed v of the barge. The resistance to the motion of the barge through the water is negligible at low speeds. F'ed = 4.4 km/h 7.1 Mg 398 Mg- Answer: v = i km/harrow_forward
- Air is exhausted from the fixed jet engine at 20 kg/skg/s with a velocity of 420 m/sm/s while it is being tested with an attached brake deflector. Determine the magnitude of the force in each of the two supporting links needed to hold the deflector in the position shown inarrow_forwardA relative airflow of 50 ft/s is flowing around the cylinder which has a diameter of 3 ft, and a length of 8 ft. Determine the total lift it creates when it is rotating at a rate of 1200 rpm at standard sea level.arrow_forwardGiven a 1400 kg car traveling along a route with an increasing vertical profile y=0.0003x^2. Determine the x-component of the car's velocity (m/s) and the total force (kN) if the constant velocity is 30 m/s and the distance is 210m. Hint: A line's slope is equal to tan theta, where theta is an angle measured from the x-axis.arrow_forward
- A jumbo jet airplane has a mass of about 400,000 kg when fully loaded with over 400 passengers and takes off at a speed of 250 km/h. Determine the takeoff speed when the airplane has 150 empty seats. Assume each passenger with luggage is 140 kg and the wing and flap settings are maintained the same.arrow_forwardProb. 15-1 15-142. The 12-Mg jet airplane has a constant speed of 950 km/h when it is flying along a horizontal straight line. Air enters the intake scoops S at the rate of 50 m/s. If the engine burns fuel at the rate of 0.4 kg/s and the gas (air and fuel) is exhausted relative to the plane with a speed of 450 m/s, determine the resultant drag force exerted on the plane by air resistance. Assume that air has a constant density of 1.22 kg/m³. Hint: Since mass both enters and exits the plane, Eqs. 15-28 and 15–29 must be combined to yield dv dm. dm; ΣF, - m Vple dt + vpli dt dt v = 950 km/h %24arrow_forwarddrag is 125 kN and the flight path angle is 6°. Determine the angle of attack and the thrust required to maintain a steady flight. Infer the effect of thrust on the aero plane's weight.arrow_forward
- Using a conservation of momentum equation, show that the force on the hemispherical vane is twice that of the force on the flat vane ?arrow_forwardThe sports car has a mass of 2.0 Mg and accelerates at 6 m/s², starting from rest. (Figure 1) Part A If the drag resistance on the car due to the wind is Fn = (10v) N, where v is the velocity in m/s, determine the power supplied to the engine when t = 5 s. The engine has a running efficiency of e = 0.68. Express your answer to three significant figures and include the appropriate units. μΑ P = Value Units Submit Request Answer Provide Feedback Figure 1 of 1 >arrow_forwardThe plane has a mass of 6.5 Mg and is propelled using two jet engines. The exhaust from the engine measured relative to the plane is 900 m/s, and the steady mass flow is 56 kg/s. 30% Part A If the plane lands with a horizontal touchdown speed of 60 m/s when the braking deflector is engaged, determine the speed of the plane 4 s after it has landod. Negloct rolling resistanco of the landing goar and the rate at which the fuol is consumed. Express your answer to three significant figures and include the appropriate units.arrow_forward
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