Mechanical Engineering Quiz

What is the difference between PRV and PSV?

7. Sealed Bearings:
A sealed bearing is mainly used to:
A) Prevent entry of contaminants and retain lubricant
B) Increase bearing diameter
C) Increase load capacity
D) Reduce noise only

3. Lubrication:
The main purpose of lubrication in a bearing is to:
A) Reduce friction and wear
B) Increase load
C) Increase bearing size
D) Reduce speed

1. Bearing Basics:
Which type of bearing is mainly used to support radial loads only?
A) Ball Bearing
B) Roller Bearing
C) Thrust Bearing
D) Journal Bearing

Q5. Heat Transfer
A plane wall of thickness 0.2 m has thermal conductivity k = 50 W/m·K.
If the wall faces are kept at 400°C and 100°C, calculate the heat flux (q).

Q4. Theory of Machines
A flywheel stores 2000 J of energy when its speed changes from 210 rpm to 190 rpm.
Find the moment of inertia (I) of the flywheel.

Q3. Fluid Mechanics
Water flows through a pipe of diameter 0.1 m with velocity 4 m/s.
Find the Reynolds number if kinematic viscosity (ν) = 1 × 10⁻⁶ m²/s.

Q2. Thermodynamics
An ideal gas is compressed isothermally at 300 K from volume 0.1 m³ to 0.025 m³.
The gas mass = 0.5 kg, R = 0.287 kJ/kg·K.
Find the work done during compression.

Q1. Strength of Materials
A steel rod of length = 2 m, cross-sectional area = 200 mm², is subjected to a tensile load of 40 kN.
If E = 200 GPa, find the elongation of the rod.

Q2. In a four-stroke petrol engine, which stroke involves the spark plug firing?
a) Intake stroke
b) Compression stroke
c) Power stroke
d) Exhaust stroke