Indiana Joes has got himself in a pickle. He\'s standing on one side of a 6m wid
ID: 2123722 • Letter: I
Question
Indiana Joes has got himself in a pickle. He's standing on one side of a 6m wide river with a hungry looking crocodile staring up at him from below. The bad gys are chasing him so he needs to get accross fast! the banks of the river are each 2m above the river. indy hooks a branch with his whip and begins to swing across. The branch is 6m abobe the river and is exactly halfway across it.
Picture given with the problem.
http://i.imgur.com/2kTP6cd.pn
A. How far above the menacing croc will indy be when he reaches that midpoint?
B. How fast will indy be going when he reaches that midpoint, given that he pushed off with a little speed boost of 2m/s when he first jumped?
Oh no! Just as the moment he's halfway across, a 9kg monkey drops onto him from above, upset that indy is disturbing the tree. Indy, whose mass is 100kg, is cool under pressure, so he doesnt lose his grip. but his plan has no changed due to this collision with the monkey. Indy does some quick thinking.
C. First of all. what type of collision is it, assuming that the moneky grabs on to indy?
D. How fast will indy (and the monkey latched onto him) be traveling after the collision? Hint: the moneky dropped down vertically with no initial horizontal speed.
E. Does indy still have enough energy to make it back up to the opposite bank, or is he doomed?
Explinations for each would be great!
Thanks
Indiana Joes has got himself in a pickle. He's standing on one side of a 6m wide river with a hungry looking crocodile staring up at him from below. The bad gys are chasing him so he needs to get accross fast! the banks of the river are each 2m above the river. indy hooks a branch with his whip and begins to swing across. The branch is 6m abobe the river and is exactly halfway across it. How far above the menacing croc will indy be when he reaches that midpoint? How fast will indy be going when he reaches that midpoint, given that he pushed off with a little speed boost of 2m/s when he first jumped? Oh no! Just as the moment he's halfway across, a 9kg monkey drops onto him from above, upset that indy is disturbing the tree. Indy, whose mass is 100kg, is cool under pressure, so he doesnt lose his grip. but his plan has no changed due to this collision with the monkey. Indy does some quick thinking. First of all. what type of collision is it, assuming that the moneky grabs on to indy? How fast will indy (and the monkey latched onto him) be traveling after the collision? Hint: the moneky dropped down vertically with no initial horizontal speed. Does indy still have enough energy to make it back up to the opposite bank, or is he doomed? Explinations for each would be great!Explanation / Answer
Part A)
From the geometry, the length of the whip to the branch is found from the pythagorean theorem
l^2 = 3^2 + 4^2
l = 5 m
Thus, at the midpoint, Indy will be 1 m above the water since the water is 6 m below the branch and his whip is 5 m long
Part B)
Apply conservation of energy
mgh = .5mv^2 (mass cancels)
(9.8)(1) = (.5)(v^2)
v = 4.43 m/s
Part C)
This collision is perfectly inelastic since the monkey hangs on and he and Indy become one mass
Part D)
By conservation of momentum
(100)(4.43) = 109(v)
v = 4.06 m/s
Part E)
Unfortunalely now Indy is doomed. He need to climb 1 m, but...
.5mv^2 = mgh
(.5)(4.06^2) = (9.8)(h)
h = .842 m - does not quite make it, but I am sure Indy will think of something....