Questions and Answers Flashcards
6 cards from real MECHANICAL APTITUDE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Questions and Answers flashcards as text
What simple machine is a screw an example of?
Answer: An inclined plane wrapped around a cylinder
A screw is an inclined plane (thread) wrapped helically around a cylinder. Each thread acts like a ramp, converting rotational motion into linear force with high mechanical advantage.
If two gears are meshed and the driver has 15 teeth while the driven has 45 teeth, how many times does the driver rotate for each rotation of the driven gear?
Answer: 3 times
The gear ratio is 45/15 = 3. The smaller driving gear must rotate 3 times to turn the larger driven gear once. This arrangement provides speed reduction and torque multiplication.
What is the difference between speed and velocity?
Answer: Velocity includes direction, speed does not
Speed is a scalar quantity (magnitude only — how fast something moves), while velocity is a vector quantity (magnitude and direction — how fast and in what direction). An object moving at 50 km/h north has the same speed as one at 50 km/h south, but different velocities.
What keeps a satellite in orbit around Earth?
Answer: The balance between gravity pulling it inward and its forward velocity
A satellite orbits because its forward velocity creates a tendency to fly off in a straight line, while gravity constantly pulls it toward Earth. These two effects balance perfectly so the satellite continuously falls around Earth without getting closer or farther.
What happens to the volume of a gas when its pressure doubles (at constant temperature)?
Answer: Volume halves
According to Boyle's Law, at constant temperature, the volume of a gas is inversely proportional to its pressure (P₁V₁ = P₂V₂). Doubling the pressure halves the volume.
What is mechanical resonance?
Answer: When an external frequency matches an object's natural frequency, causing large oscillations
Mechanical resonance occurs when the frequency of an external vibration matches an object's natural frequency, causing increasingly large oscillations. This can be destructive if not controlled, as demonstrated by the famous Tacoma Narrows Bridge collapse.