What is the magnitude and difrection of the acceleration?

AI Thread Summary
To determine the acceleration of a 5kg mass acted upon by three forces (20N north, 30N west, and 45N east), one must calculate the x and y-components of each force and sum them to find the resultant force. The gravitational force between a 100kg and a 200kg object, 10m apart, can be calculated using Newton's law of universal gravitation with the given constant. The question about rocket propulsion relates to Newton's 3rd law, emphasizing the action-reaction forces involved in thrust. For balanced forces, the correct answer regarding motion is A) no change in translational motion. Understanding these concepts is crucial for solving the problems presented.
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1. three forces act on a 5kg mass. the forces are 20n north, 30n west, 45n east. what is the magnitude and direction of the acceleration?

- how do I set this up? i am kinda lost on thsi one.

2. what is the gravitational force between a 100 kg object and a 200kg object if centers of mass are 10m apart. g= 6x10^-11 N m^2//kg^2

- this one too.. i don't know how i set this up.

3. describe the forces in terms of Newton's 3rd law that propel a rocket?

- what is this mean? i know Newton's 3rd law is for every action there is an equal and opposite reaction but what is this question asking?

4. under a balanced force there A) no change in translational motion B) No rotational motion C) no inertia D) all of above

- I am guessing it's C?


Any help would be greatly appreciated. It's not like I didn't try. None of this problems were done in class and I can't find similar examples either. :(
 
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1. Calculate the x and y-components of each force. Then add all the x-components together. Do the same for the y-components. You will then have the components of the resultant force. From which you can calculate the acceleration in each of these directions using Newton's 2nd law.
 
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