WTMA Center of Gravity and Stability 5

Question 1

A worker hangs a heavy tool bag on one handle of a wheelbarrow. Compared to placing the bag in the bucket, this makes the wheelbarrow:

Accepted Answer

Harder to control because the center of gravity shifts sideways

Answer

Hanging weight on one handle shifts the center of gravity to one side, creating an unbalanced lateral torque that is difficult to counter.

Question 2

A ship's ballast tanks are filled with water low in the hull during a storm. This practice:

Accepted Answer

Lowers the center of gravity, increasing stability in heavy seas

Answer

Filling low ballast tanks adds mass near the keel, lowering the center of gravity and improving the ship's righting moment in rough conditions.

Question 3

A solid cylinder and a hollow tube of the same outer diameter, height, and total weight are placed on an inclined surface. Which is more stable against rolling?

Accepted Answer

The hollow tube, because its mass is concentrated at the outer edge increasing rotational inertia

Answer

The hollow tube has more mass concentrated at the outer radius, giving it higher rotational inertia and greater resistance to changes in rotation.

Question 4

A tower crane has a long horizontal arm (jib) with a counterweight on the short end. If a very heavy load is suspended near the tip of the long end, the crane operator should:

Accepted Answer

Keep the load as close to the mast as possible to avoid tipping

Answer

Keeping the load close to the mast reduces the moment arm, decreasing the tipping torque on the crane's base.

Question 5

A vending machine being moved on a dolly is tilted back to about 45 degrees. At this angle, it is:

Accepted Answer

At high risk of tipping because the center of gravity is near the edge of the support base

Answer

At 45 degrees, the center of gravity of a tall object is close to or beyond the edge of the dolly's support base, making tip-over likely.

WTMA - Wiesen Test of Mechanical Aptitude Practice Test

WTMA - Wiesen Test of Mechanical Aptitude Practice Test

WTMA Center of Gravity and Stability 5