Question by xovotejuiceyxo: I need homework help. I don’t understand at all. please help (: [science- physics]?
you are suppost to use the equations and make the appropriate subsitutions.
1. If the masses are not changed, but the distance of serperation is reducded to 1/4 the original distance, what happens to the force?
2.If both masses are doubled and the distance of separation is doubled, show what happens to the force.
3. If one of the masses is doubled , the other remains unchanged, and the distance of serperation is triples, show what happens to the force.
4. Consider a pair or binary stars that pull on each other with a certain force. Would the force be a larger or a smaller mass of each star were three times as great and if their distance apart wee three times as far? show what the new force will be compared to the first one.

Best answer:

Answer by MeNeedHelp
Here are my hints for you to solve it =]

1. If the masses are not changed, but the distance of serperation is reducded to 1/4 the original distance, what happens to the force?
F = ma
mass is the same the key is “a”
acceleration can be positive or negative negative acceleration = decelerate

so therefore shorter distance to stop would mean higher deceleration =] so right off the bat you know decrease in distance increases deceleration to get something to stop which means greater force

V1 = “some value”
V2= 0
d= given
a = ?
using kinematic equations + momentum equations in your textbook you should be able to solve it with breeze rearrange and back and forth substituion =)

2.If both masses are doubled and the distance of separation is doubled, show what happens to the force.

once again same thing as before

F= ma

mass_new = 2Mass_old

however Distance doubled. so therefore deceleration decreases…

so F = (2*mass)*(calculated acceleration/decelleration)
using kinematic equations and whatevers given should get you the results

the rest of the questions is the same thing =]

4. Consider a pair or binary stars that pull on each other with a certain force. Would the force be a larger or a smaller mass of each star were three times as great and if their distance apart wee three times as far? show what the new force will be compared to the first one.

for this one.. you would have to use gravitational force in your textbook (force of gravity)
equation

Fg = Gm1m2/r^2
r^2 is the centre to centre distance apart

punch in the values for normal distance and mass and compare it when you punch in the values for the stated in the question

What do you think? Answer below!

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