Compute the order of magnitude of the mass of (a) a bathtub filled with water, and (b) a bathtub filled with pennies. In your solution list the quantities you estimate and the value you estimate for each.

Answer 1

The average "one person" bathtub holds about 80 gallons but is filled to only about 50 gallons. One gallon of water. weighs about 7.5 pounds.

If you filled it with pennies, the contents would weigh about 6 times as much. Remember that pennies are mostly zinc, with only a thin layer of copper.

They don't say if you are supposed to include the weight of the empty tub.

Answer 2

The weight of a typical empty bathtub, porcelain on steel, is about 350 lb.