Question

I GIVE MEDALS.
Two asteroids are 75,000 m apart. One has a mass of 8 107 kg. If the force of gravity between them is 1.14 N, what is the mass of the other asteroid?

A. 3.4 X 10^11 kg
B. 1.2 X 10^12 kg
C. 1.2 X 10^10 kg
D. 8.3 X 10^12 kg

Answer 1

Haven't we done this once?

F = k m M / r^2 etc.

Answer 2

ok ,
We have been given
r = distance between the asteroids = 75000 m
and mass of one asteroid (m1) = 107 kg
m2 = mass of second asteroid (to be found)
and if the force of gravity between them ,is F = 1.14 N
also we know that Force of gravity is
F = Gm1m2/r^2
therefore,

1.14= G*107*m2/(75000)^2
m2 = 1.14 * 75000 * 75000 /107G
(lemme calculate this :P, and btw i m guessing that it is a typo in your question u have type mass 8 107 kg <--- i m guessing that extra is a typo rite?) :P

Answer 3

Its supposed to be 8X10^7 kg, sorry @CyberShadow

Answer 4

Gothca!
Ok so that makes our equation
m2 = 1.14 * (75000)^2 /6.6 * 10^-11 * 8 * 10 ^7
so after all the calculatioin
m2 = 121.44 * 10^10 (approximately)
i m not sure abt my calculation tho ,, u can try calculating it on ur own :)

Answer 5

Is there any way to simplify it?
Those are way off from my choices.
Ill calculate it and see if i get the same thing tho @CyberShadow

Answer 6

actually the calculation is corect

Answer 7

121.4 * 10^10 = 1.2 * 10 ^12

Answer 8

sorry dint read ur options first time

Answer 9

It's fine!
how did you multiply 10^10? @CyberShadow

Answer 10

ok see , we had 121.4 *10 ^10 right?
then in the options we have 1.2
so i converted 121.4 into 1.2
and how can we do that? by diving it by 100 i.e 10^2
and if we r diving it by 100 , we also have to multiply it by 100
so
\[121.4\div(10^{2})\times10^{2}*10^{10}\]
so that make it 1.2 * 10 ^ 12
got it?

Answer 11

How did you get 10^2, was it just random? @CyberShadow

Answer 12

what wud u do, to convert 121.4 to 1.2 ?

Answer 13

oh, you divide.
alright i got it cx
thanks! @CyberShadow

Answer 14

No probs :)