Get premium membership and access revision papers, questions with answers as well as video lessons.

Basic Mechanics Question Paper

Basic Mechanics

Course:Bachelor Of Electrical And Electronics Engineering

Institution: Moi University question papers

Exam Year:2011

BASIC MECHANICS

(Characteristic gas constant, R = 287 J/kg K; 1 mbar = 100 N per square metre; 1 knot = 0.514 m/s)

1. An aircraft cruises in straight, level flight at 450 km/h where the drag force is 6 kN. If the power supplied to the propeller shaft is 1 MW, find the propeller efficiency.

2. An aircraft of mass 1800 kg flies at a steady speed of 180 km/h in straight, level flight. The lift to drag ratio is 7 and the propeller efficiency is 80 percent. Find the power delivered to the propeller shaft.

3. An 11 t aircraft flies at 1180 km/h in steady, level flight with the engine exerting a thrust of 12 kN. Find the ratio of lift to drag and the power output.

4. A supersonic aircraft of mass 175 t is flying steadily in straight, level flight at Mach 1.8 at an altitude where the speed of sound in air is 584 knots. If the thrust is 150 kN, find the lift to drag ratio and the power output.

5. A single-engined turbofan, mass 10 t, flies at a steady speed 500 knots in straight, level flight. The jetstream leaves at a mean speed of 800 m/s relative to the engine and the mass flow rate of air through the engine is 55 kg/s. Find the drag force. If afterburners are employed to increase the thrust by 80 percent and the flight path is kept level, what is the time taken to travel 10 km and the speed reached in knots?

6. An aircraft makes a steady gliding descent without power. Show that the angle of glide is dependent of the weight of the aircraft and find its value if the lift/drag ratio is 10.

7. A jet plane of mass 4200 kg climbs a 20 degree to the horizontal when the propelling and drag forces as 24 kN and 4 kN respectively, along the line of flight. If the speed at the beginning of the climb is 250 m/s, find the speed when the plane gains 800 m in altitude.

8. A propeller driven aircraft of weight 24.5 kN climbs at a steady speed of 200 km/h at an angle of 15 to the horizontal. The drag force is 6 kN. Find the thrust along the kind of flight. If the propeller efficiency is 80 percent and the engine overall efficiency is 30 percent, what is the energy input to the engine?

9. The engine of a jet plane tested on a stationary rig gave a ''static'' thrust of 98 kN. The engine is fitted to a plane of mass 16000 kg. Assuming the same total thrust as for the static conditions and a steady resistance of 15 kN in flight, find the angle of climb possible
a. At constant speed,
b. When accelerating at 3 metres per square seconds.

Basic Mechanics Question Paper

More Question Papers

Popular Exams