WTMA - Wiesen Test of Mechanical Aptitude Center of Gravity and Stability Questions and Answers — Questions and Answers
Question 1: A modern race car is designed to be very low to the ground with a wide wheelbase. What is the primary physical principle behind this design for enhancing stability?
- To increase its overall mass for better road grip.
- To reduce aerodynamic drag and improve top speed.
- To lower its center of gravity and widen its base of support. (Correct answer)
- To make it easier for the driver to enter and exit the vehicle.
Correct answer: To lower its center of gravity and widen its base of support.
Stability is increased by lowering an object's center of gravity and widening its base of support. [8, 9] A low and wide design makes the race car much more resistant to tipping or rolling over, especially during high-speed turns. [14]
Question 2: An object is in a state of 'unstable equilibrium' if, after being slightly displaced, its center of gravity:
- Remains at the same height.
- Returns to its original, lower height.
- Moves to a new position but at the same height.
- Continues to move to an even lower position, causing it to topple. (Correct answer)
Correct answer: Continues to move to an even lower position, causing it to topple.
An object in unstable equilibrium, like a cone balanced on its tip, has its center of gravity in the highest possible position. [9] Any slight displacement will lower the center of gravity, and the object will continue to fall over rather than return to its original position. [5, 10]
Question 3: Which of the following actions would MOST improve the stability of a tall, empty filing cabinet?
- Placing heavy items in the bottom drawer. (Correct answer)
- Placing heavy items in the top drawer.
- Ensuring all the drawers are closed.
- Painting the cabinet a different color.
Correct answer: Placing heavy items in the bottom drawer.
Placing heavy items in the bottom drawer effectively lowers the cabinet's overall center of gravity. A lower center of gravity significantly increases an object's stability and makes it less likely to tip over. [8, 9]
Question 4: A worker is carrying a long, heavy plank of wood on his shoulder. To make it easiest to balance, where should the plank's center of gravity be located?
- As far in front of his shoulder as possible.
- Directly above the point of support (his shoulder). (Correct answer)
- As far behind his shoulder as possible.
- The location of the center of gravity does not affect balance.
Correct answer: Directly above the point of support (his shoulder).
For an object to be balanced, the point of support must be aligned vertically with the object's center of gravity. [3] If the center of gravity is directly above the worker's shoulder, the weight is evenly distributed, and no turning force (torque) is created, making it stable and easy to carry.
Question 5: Imagine two solid, identical blocks. Block A is a short, wide cube. Block B is a tall, narrow rectangle standing on its end. Which statement is correct?
- Block B is more stable because it is taller.
- Both blocks have equal stability.
- Block B is more stable because it has a smaller base of support.
- Block A is more stable because it has a lower center of gravity and a wider base of support. (Correct answer)
Correct answer: Block A is more stable because it has a lower center of gravity and a wider base of support.
Stability is determined by two main factors: a low center of gravity and a wide base of support. [6, 8] The short, wide cube (Block A) has both a lower center of gravity and a wider base compared to the tall, narrow block (Block B), making it significantly more stable.
Question 6: A tightrope walker often carries a long pole. How does this pole help them maintain balance?
- The pole's weight pushes them down onto the rope more firmly.
- It makes the walker more aerodynamic.
- It effectively lowers the walker's combined center of gravity. (Correct answer)
- It increases the walker's total mass, making them harder to move.
Correct answer: It effectively lowers the walker's combined center of gravity.
The long pole, especially if it has weights at the ends and is held low, lowers the combined center of gravity of the walker and the pole. [6] A lower center of gravity increases stability, making it easier for the walker to make small adjustments and stay balanced on the narrow rope. [8]
WTMA - Wiesen Test of Mechanical Aptitude Center of Gravity and Stability Questions and Answers
A modern race car is designed to be very low to the ground with a wide wheelbase.
What is the primary physical principle behind this design for enhancing stability?