The gravitational force between two spheres in outer space is 1000 n. how large would this force be if the mass of each sphere were doubled and the distance between them were doubled?

The force will remain same if the mass of each sphere is doubled and the distance between them is doubled as well.

The force of gravitation between two spheres is given by

m1= mass of first object

m2= mass of second object

r= distance between the masses

Now if each mass is doubled and the distance r is doubled as well

F'=

so F'= F

so the force remains same and is equal to 1000 N.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s

statement #3 on andre"s list is false.