Physics in the Real World (2017 NYD) Mystery Cache
Physics in the Real World (2017 NYD)
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Difficulty:
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Terrain:
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Size: 
(regular)
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A quick little mystery to go along with the 2017 New Years Day Brunch with Loch Cache event.
Background:
Each year I try to create a puzzle to be released on New Years Day that is a bit challenging. This year is no different unless you are a physics nut.
Below are eight individual physics problems similar to the ones my freshman classes have solved on my quizzes or tests. The first four added together (ignoring the differences in units) will give you the last five digits of the west coords and the last four of them added together (ignoring the differences in units) will give you the last five digits of the north coords. Please follow the directions for the addition of the results. A couple of givens to be stated:
- All problems take place on earth unless otherwise stated and therefore the pull of gravity is 9.8 m/s/s;
- All problems involving displacement adhere to forward, right, up, east and north as positive and backwards, left, down, south and west as negative;
- Answers for each individual problem should be rounded to three digits to the right of the decimal;
- Assume negligible friction and/or air resistance unless otherwise stated;
Cache Puzzle:
A - Momentum
A 5.51 kg skateboard is moving at a velocity of 4 m/s. What is its momentum?
B - A - Upward Launch
A ball is tossed straight up into the air with an initial velocity of 12.25 m/s, what is the velocity of that ball after 2.5 seconds?
C - Impulse
If a 1.514 kg book sitting on a table is pushed by a student until it reaches 0.5 m/s what is the impulse?
D - Change of momentum
Mr. Lochrie lines up a straight shot on his pool table. He is going to use the cue ball to strike (and hopefully sink) the eight ball. Just prior to the collision the cue ball has a velocity of 3.0 m/s and after the collision it has a velocity of just 1.0 m/s. The cue ball has a mass of 170g and the eight ball has a mass of 160g.
Expressed in kg•m/s what is the momentum of the eight ball after the collision?
E - Average Velocity
Average velocity is different than speed because it represents displacement over time. Calculate the average velocity of a car that travels 60 mph east for one hour, then 30 miles north over the course of one hour, then 45 mph for 45 minutes headed east, then westward for 20 minutes at 90 mph; followed by heading south for two hours at 15 mph and wrapping up heading east for 15 minutes at 60 mph.
F - Net Force
An object at rest will stay at rest unless acted upon by an outside, unbalanced force.
A box on loading dock has a mass of 100 kg. Calculate the net force upon a crate under the following forces: gravity with a force of 980N; normal force of 980N, a man pushing (applied) on the crate from the left at a force of 297.384N; a second man pushing on the crate from the right with a force of 50.792N and a man pulling on a rope next to the crate with a force (tension) of 100 N.
G - Change of Velocity
A car is traveling at a velocity of 100 kmph northward. The driver sees a train traveling at a velocity of 150 kmph southward. The driver of the car changes his velocity to match that of the train over a period of 25 seconds. What is the car’s change of velocity?
H - Free Fall
A ball is dropped from a cliff and lands after four seconds. If there is no other force applied to the ball other that gravity, what is the average speed of the ball over the four seconds?
The Cache:
You are looking for a regular size box hidden in a regular manner in a regular hiding area. Well regular according to Loch Cache standards.
Enjoy the area and the caching.
Good luck and good caching,
Loch Cache
Congrats to sloth96 and T13 and EvilTree for FTF! And a shout out to Mrs. T13 for the assist!!!!!!!!!
Additional Hints
(Decrypt)
227.786 srrg sebz cnexvat sbe n arneol pnpur.