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#### merper

##### Guest

**Plz help - # 1 and #2 are due tomorrow**

Im in an engineering physics honors class and I am having trouble figuring out how to go about solving a few of the problems that I have encountered.

1) A system has 2 blocks m1 and m2 ( on a flat frictionless plane), connected by a massless spring, with spring constant k. m1 is against a wall. If at t0, m2 is pushed towards m1, compressing the spring from its original length of L to L/2, find the motion of the spring in relation to time.

I am not at all sure how to go about this. My book converts the motion into simple harmonic motion involving coswt and such for a similar problem, but I'm not sure how to use this as I never learned in high school.

2) A fisherman is sitting at the stern of a boat, and both the boat and the man are at rest. The fishermen than moves towards the bow, and eventually, the boat and the man are at rest again. Find the displacement of the boat assuming that the motion of the boat in the water is turbulent, i.e., it is characterized by a friction force that is proportional to -v2, where v is the velocity of the boat with respect to water. You may assume some simple model for the process if necessary (for example, the man jumps, and after a bit of a ballistic flight, lands on the bow).

Not sure how the friction affects the situation.

3) A rope of Mass M and length L lies on a frictionless table. A small portion of the rope, L0 is hanging through a hole in the table. Initially the rope is at rest.

a) find a general equation for x(t) the length of the rope through the hole.

The answer they havee is crazy : Ae^($t) + Be^($t) = x, also

$^2 = g/l where $ is a symbol standing for gamma.

Im not sure where they pulled this from

b) evaluate the constants A and B so initial conditions are satisfied

No clue

plz help me get this - this class is making me hate physics

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