# Calculate Time to Move 2 Isolated Masses: Gravitational Field

• Rasine
In summary, the problem involves two masses, M1 = 2.20 kg and M2 = 607 kg, initially at rest and a distance of 171 cm apart. The only force acting is gravitational attraction. To calculate the time it takes for M1 to move from 171 cm to 169 cm from M2, the formula F=G(m1m2)/r^2=m1a is used. After simplifying, the equation becomes a=6.67x10^-11*607/(1.7)^2. Then, using the equation x=xo+vot+.5at^2 and considering the acceleration to be constant, the time can be calculated. However, dividing the distance by 2 is

#### Rasine

Two isolated masses, M1 = 2.20 kg and M2 = 607 kg are initially rest, a distance d = 171 cm apart. Their gravitational attraction is the only force acting. Calculate the time it takes for M1 to move from that distance to 169 cm from M2. Assume that M2 does not move and that the force is constant over that small distance, and equal to that at 170 cm.

i want to use F=G(m1m2)/r^2=m1a so Gm2/r^2=a

6.67x10^-11*607/(1.71/2)^2=a

then when i have a i am going to use x=xo+vot+.5at^2 to find t

Actually, I think I will stick with my original advice. Like I said, you shouldn't be dividing the distance by 2. If the force is constant, I would think you take it at the 1.71 m.

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At a blush. I think the decision to halve the 171 is mistaken

Obviously you are supposed to consider that the acceleration is constant, or else you would have to deal with some differential equations.

well the problem tells you to use 170,
so we have :
f=6.67E-11*607*2.2/.170^2=?

Divide by 2.2 to get a, then use kinematics

PS oops that's meant to be 1.7

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ok i will try that

## 1. How do you calculate the time it takes for 2 isolated masses to move in a gravitational field?

To calculate the time it takes for 2 isolated masses to move in a gravitational field, you can use the formula: Time = (π/4) * √(d^3/GM), where d is the distance between the masses, G is the gravitational constant, and M is the combined mass of the two objects.

## 2. What is the gravitational field?

The gravitational field is a region of space around a mass where other objects experience a force of attraction towards the mass. It is created by the mass and its strength is determined by the mass and distance from the mass.

## 3. How does the distance between the masses affect the time it takes for them to move?

The time it takes for 2 isolated masses to move is directly proportional to the distance between the masses. This means that as the distance between the masses increases, the time it takes for them to move also increases.

## 4. What are isolated masses?

Isolated masses are objects that are not influenced by any external forces, such as friction or air resistance. In the context of calculating time to move in a gravitational field, it refers to two objects that are only affected by their own gravitational attraction to each other.

## 5. Can this formula be used for any two masses?

Yes, this formula can be used for any two masses, as long as they are isolated and only influenced by their own gravitational attraction to each other. However, it is important to note that this formula is based on the assumption that the masses are point masses, meaning that their size is negligible compared to the distance between them.