Fun With Fundamentals: Problem 225

May 1, 2000
Will this engineer's crimes of passion be exposed? John Cox of Twin Falls, Idaho gives us the grisly details

Shallow plot

Problem 225 - Will this engineer’s crimes of passion be exposed? John Cox of Twin Falls, Idaho gives us the grisly details.

Digger Pyle, a soils engineer becomes enraged when his boss refers to soil as dirt.

After obsessing about the callous remark for days, Pyle decides his boss must die. Late one night, Pyle visits the local landfill to take some soil measurements. He determines that the soil’s natural density is 85% of maximum and reaches 90% of maximum when handtamped upon back-filling.

Pyle needs to know how deep a hole to dig to avoid leaving a mound or depression at the surface. The boss’s volume is 2 ft2 and the hole must be 2 ft x 6 ft. Will Digger be able to cover his dirty deed?

Solution to April's problem 224- You’re all wet if you didn’t agree that Lacker was right for a change. Here’s why his mop stayed dry:

The key is that for the boat to float, it must displace a volume of water, the weight of which is equal not only to the weight of the boat but also to its cargo.

Solving for the volume of the bucket:

and from this the weight of the bucket:

We can determine the volume of water being displaced by the weight of the anchor in the boat:

And the net volume displaced after the anchor is dropped:


The water level actually went down, it looks like Durdee was the one to take the bait this time.

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