Sundial (or how to check the work of your contractor)

[brak]

Here is a little test that I found amusing. A contractor that shall, in this thread, remain unnamed, worked on my boat. The part of the job pictured here was done in one day.

Boat bow is facing exactly North-West (315 degrees true) and is located at about 39N lattitude. The inverted "swan neck" tube in the middle points to the stern with it's open end. First picture is taken when the job started, second when it was finished.

Can you determine how much time passed between these photos? This is also a good excercise for those celestial navigation skills.

Begin.


End.

[N0NJY]

I'm seeing that they started at 3ish in the after noon and finished in less than two hours? Roughly?

(let me know if I am close or right in PM! Save it for the others to answer too!)

[denby]

Looks like 1pm to 3pm. Pm me and let me know, thanks

[brak]

I don't have the true answer (except for my own estimate). As you may have guessed, contractor claims a number that is somewhat different

[JohnRPollard]

Originally Posted by brak

Can you determine how much time passed between these photos?

I would have answered "3 hours". First shot taken roughly at noon, second at 3pm-ish.

??

[brak]

Keep'em coming. I will post the number of hours he charged me for later in the evening. (It ain't that funny when you have to pay for it, but hey - gotta find entertainment everywhere)

[sailingdog]

My guess is that he started around noon, since the shadow is pointed almost due north, and ended about three hours later, with the shadow pointed northeast.

[hellosailor]

The sun "moves" 15 degrees per hour, the shadow has shifted maybe 45 degrees max, so let's say he billed you for nearly three hours. Or, was it an overnight job?

What I'd like to know is where you got the power pack for the little Preval sprayer. I bought one at HD once upon a time, and now they don't remember ever selling them. Handy little gizmo though!

[Bene505]

What time of year was it? Was it recent?

[AllThumbs]

Not sure about the time but in his/her defence it doesn''t look like the pic was taken before he/she started (some prep done), nor does it look like he/she was totally done when the last pic was taken (cleanup).