Past Papers Basic Mechanical Technology

By: Prof. Fazal Rehman Shamil

Guess Paper 1: Basic Mechanical Technology Fall – 2020 Past Papers

University Name – Confidential

NOTE: Q.1 is compulsory, attempt any four questions from the remaining. All questions carry equal marks. Phones and other Electronic Gadgets are not allowed.

Time Allowed: 3 hours

Total Marks:    70, Passing Marks (35)

Q1. Fill in the blanks:
1. Hooke’s law holds good up to ¬___________________________.
2. The ratio of linear stress to linear strain is called ______________________.
3. The modulus of elasticity for mild steel is approximately equal to ___________________.
4. When a hole of diameter ‘d’ is punched in a metal of thickness `t’, then the force required to punch a hole is equal to ______________________.
5. The material suitable for the belts used in agricultural equipments is _______________________.
6. When the speed of belt increases, the power transmitted will¬ ___________________________.
7. In a crossed belt drive, the shafts are arranged parallel and rotate in the ________________ directions.

Q2. Explain Torsion in detail and also derive Torsion Equation.

Q3. A cast iron pulley transmits 20 kW at 300r.p.m. The diameter of pulley is 550 mm and has four straight arms of elliptical cross-section in which the major axis is twice the minor axis. Find the dimensions of the arm if the allowable bending stress is 15MPa. Mention the plane in which the major axis of the arm should lie.

Q4. Explain Flywheel and Discuss Coefficient of fluctuation of Speed.

Q5. Explain Mechanical Properties of a Material in details.

Q6. Define Clutch & explain types of Clutch in detail.

Q.7 A line shaft rotating at 200r.p.m. is to transmit 20 kW. The shaft may be assumed to be made of mild steel with an allowable shear stress of 42MPa. Determine the diameter of the shaft, neglecting the bending moment on the shaft.

Q.8 Write short note on the following:
1. Belt & Creep of Belt.
2. Stress & Strain and its types.

Guess Paper 1: Basic Mechanical Technology Spring – 2020 Past Papers

University Name – Confidential

NOTE: Q.1 is compulsory, attempt any four questions from the remaining. All questions carry equal marks. Phones and other Electronic Gadgets are not allowed.

Time Allowed: 3 hours

Total Marks:    70, Passing Marks (35)

Q1. Fill in the blanks:

1. 1 MPa = ____ N/m2 = ____ N/mm2.
2. A localized compressive stress at the surface of contact between two members of a machine part, that are relatively at rest is known as _______________.
3. Factor of safety = _________________.
4. The ratio of the change in volume to the original volume is known as ______________.
5. Sometimes, the frictional grip between the belts and the pulleys becomes insufficient. This may cause some forward motion of the driver without carrying the belt with it. This is called ________________.
6. The difference between the maximum and minimum fly-wheel speeds during a cycle is called the _____________.
7. A _________ is a machine member used to connect a driving shaft to a driven shaft so that the driven shaft may be started or stopped at will, without stopping the driving shaft.

Q2. Define Stress & Strain. Also explain its types.

Q3. A hydraulic press exerts a total load of 3.5 MN. This load is carried by two steel rods, supporting the upper head of the press. If the safe stress is 85 MPa and E = 210 kN/mm2,
Find: 1. diameter of the rods, and 2. extension in each rod in a length of 2.5 m.

Q4. Explain Torsion in detail and also derive Torsion Equation.
Q5. Explain stress-strain diagram for mild steel rod material in detail.

Q6. Define Belts & explain types of belts. Discuss material used for belts.

Q7. A cast iron pulley transmits 20 kW at 300 r.p.m. The diameter of pulley is 550mm and has four straight arms of elliptical cross-section in which the major axis is twice the minor axis. Find the dimensions of the arm if the allowable bending stress is 15 MPa. Mention the plane in which the major axis of the arm should lie.

Q8. Write short note on any two of the following:
a. Explain Clutch.
b. Explain pulley.
c. Mechanical Properties of Material