Pirate Physics 100

[Red Maria]

A friend of mine who is a physics professor gave the following quiz to his class...

Physics 100

Test 2

Fall 2005

I have been more honest than any pirate on this test.

________________________________________________________

Choose eight out of the nine following problems. Clearly X out the entire problem you’ve

chosen to ignore. Circle your choice for the correct answer. The number in [x] indicates

the correct number of significant figure to use.

1) Three forces act on a pirate captain. The first mate pulls on captain at an angle of

30o with a force of 48N; the second force, a British officer pulls on him at an

angle of 135o with a force of 64N. Finally, a saucy wench pulls on him with a

force of 36N at an angle of 225o. What is the resultant force on the pirate captain?

[2]

2800N @ 120o 53N @ 120o 53N @ 56o 15N @ 120o None of these

2) What is the energy of a 5.0kg cannonball, fired from a pirate ship at an angle of

45o with a speed of 200m/s? [2]

70,000J 70,700J 100,000N 100,000J None of these

3) A 70kg pirate, strutting at 2.0m/s the deck of his ship, slips on a mackerel. He

slides 3.0m before coming to rest. What is the coefficient of kinetic friction

between the mackerel and the deck? [2]

0.66N/m 0.068 0.67 0.068m/N None of these

4) How much power does a 50kg boatswain expend if he climbs 20m up into the

rigging of a pirate ship in 30 seconds? [2]

20,000J 330W 19,000W 330J None of these

5) What is the change in kinetic energy of the Jolly Roger (a pirate ship), mass of

10,000kg, if it is moving east at 10m/s but then heads north at the same speed? [2]

10,000J 100,000J 50,000J 0.0J None of these

6) A treasure chest weighs 1000N. What acceleration does it undergo if it is pulled

across the deck of a ship with a rope attached at angle of 30o that has a tension of

1000N. The μk of between the chest and the deck is 0.50. [2]

17m/s2 1.7m/s2 6.0m/s2 1.4m/s2 None of these

7) A cannonball is fired at an angle of 45o at a British Man O’ War. The cannonball

is moving at 150m/s when it has risen 150.0m above the cannon. How fast was it

shot out of the cannon? [2]

3,500m/s 160m/s 110 m/s 140m/s None of these

8) The elastic strap on an eyepatch has a spring constant of 5.0 N/m. It is used by a

frantic one-eyed pirate as a slingshot to throw a 100g stone at a British prison

guard. If he stretches the strap 10cm, what will be the acceleration of the stone?

[2]

5.0 m/s 5.0 cm/s 50cm/s 500m/s None of these

9) A 50g parrot hovering at 25.00m dives from that height into a bale of cotton. He

stops after traveling straight down into the bale 1.000m. How much work is done

by the cotton in stopping the parrot? [4]

12.74J 12.25J 0.000J 12.25N None of these

[Black Hearted Pearl]

Although this is a pirate test, it seems only Gunner Gary would get half these questions right. Personally, I shoot from the hip with my guts and it works well while under fire. I bet the professor didn't consider that in his equations, but kudos for him getting his students' attention.

[hurricane]

"C" for all of them for I'm all at "sea" when it comes to things nautical.

Hurricane

[Morgan Dreadlocke]

What good be advanc'd edukasion iffins the buggerin' instructor don't even know what a bleedin' parrot weighs? Me kids got scrawny parakeets weigh'n more than 50 grams. 'Ow much work be the cotton doin? All of it Lass.

The rest 'o them questions, well --- Money ar rum Lass, nuttin' fer free

[Cpt. Alva]

What is the standard flightspeed of an unladen african swallow, flying with the wind?