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**1. Homework Statement**

I find the physics book I have doesn't explain in great detail how to do these types of questions. I would like some feedback on the answers I have come up with. Thanks in advance.

Peter and John are playing a game of tug and war on a frictionless icy surface. Peter weighs 539 N and John weighs 392 N. During tthe course of the game, John accelerates toward Peter at a rate of 3.0 m/s ^2.

(a) What is the magnitude of the force that Peter exerts on John?

(b) What is the magnitude of the force that John exerts on Peter?

(c) What is the magnitude of Peter's acceleration toward John?

(d) Sarah decides to join the game as well. Now Peter pulls on Sarah with a force of 45.0 N (E), and John pulls on her with a force of 25.0 N(N). WHat is Sarah's resultant acceleration, if she weighs 294 N?

**2. Homework Equations**

magnitude of force = multiply mass by acceleration

a=appplied force /mass

**3. The Attempt at a Solution**

First I calculated John and Peter's mass by dividing the Newton weight by the force of gravity which is 9.8 m/s^2

Therefore Peter weighs 55 kg and John weighs 40 kg.

(a) I multiplied John's mass by John's acceleration

=40 kg X 3.0 m/s^2

=120 N

(b) 120 N. Based on Newton's third law that states they exert equal and opposite force on eachother.

(c) acceleration = Fapp / mass = 120 N /55 kg = 2.19 m/s (This one I am really not sure on at all)

(d) Sarah weighs 30 kg.

F net = (45 N)^2(25N)^2

= 2025 + 625

=51.48 N

Therefore to find Sarahs acceleration

a= 51.48 N/30 kg = 1.71 m/s ^2

to find the specific degrees of direction I tried to draw a free body diagram to help me viaualize this problem better.

I came up with Tan = opposite /adjacent = 45N / 25 N = 1.8

Tan-1(1.8)

=60.9 degrees

Therefore the resultant acceleration would be 1.71 m/s ^2 (N 60 degrees E)

Any feedback would be of great help.

Thanks

Pharm 89

**1. Homework Statement**

**2. Homework Equations**

**3. The Attempt at a Solution**