Forces Experienced On Moon and Earth - What is the mass?

[lola1227]

Homework Statement

an object on earth experiences a force of gravity which is 25N larger than the moon. If g(earth) = 9.8m/s^2 and g(moon) = 1.62m/s^2 .what is the mass of the object?

Relevant Equations

F=mg?

So, I decided to do

Fg=ma

I tried 25(9.8)=1.62m

m= mass

However, when i did it i got a mass of 151 but when i put it into its separate equations, the fg is not 25x larger

so fg=ma
fg=151(9.8)
= 1479.8and then fg=ma
fg=151(1.62)=
244.62

but 1479.8/244.62 is not 25 it ends up being 6.05

so i do not know where to go from here.

 

[TSny]

Let Fe represent the force of gravity experienced by the object when the object is on the earth.
Let Fm be the force of gravity when the object is on the moon.

Can you write an equation that relates the symbols Fe, Fm, and 25N?

 

[lola1227]

Let Fe represent the force of gravity experienced by the object when the object is on the earth.
Let Fm be the force of gravity when the object is on the moon.

Can you write an equation that relates the symbols Fe, Fm, and 25N?

would it be fe(25)=fm?

 

[lola1227]

Let Fe represent the force of gravity experienced by the object when the object is on the earth.
Let Fm be the force of gravity when the object is on the moon.

Can you write an equation that relates the symbols Fe, Fm, and 25N?

or with numbers (9.8)(25)=(1.62)?

 

[gneill]

I don't see anywhere in the problem that friction is involved. Why is friction mentioned in your thread title?

Edit: Thread title edited to better reflect the actual problem.

 

[TSny]

would it be fe(25)=fm?

This is not correct. You need to express the fact that fe is 25 N larger than fm.

 

[lola1227]

I don't see anywhere in the problem that friction is involved. Why is friction mentioned in your thread title?

my bad. I changed the title

 

[lola1227]

This is not correct. You need to express the fact that fe is 25 N larger than fm.

so fe+25=fm

 

[TSny]

so fe+25=fm

That's better, but still not quite correct. If fe happened to be 50 N, what would your equation give for fm? Would the result make sense?

 

[lola1227]

That's better, but still not quite correct. If fe happened to be 50 N, what would your equation give for fm? Would the result make sense?

i see. would the equation be

m(9.8)=m(1.62)+25?

 

[TSny]

i see. would the equation be

m(9.8)=m(1.62)+25?

Yes. Make sure that you feel confident with this equation.

 

[lola1227]

Yes. Make sure that you feel confident with this equation.

9.8x=1.62x+25
9.8x-1.62x=25
8.18x=25
x=3.056??
so would the mass be 3.056kg?

 

[TSny]

9.8x=1.62x+25
9.8x-1.62x=25
8.18x=25
x=3.056??
so would the mass be 3.056kg?

Yes. (I don't know if you are required to express the answer with an appropriate number of significant figures.)

 

[lola1227]

Yes. (I don't know if you are required to express the answer with an appropriate number of significant figures.)

Thank you very much for your help!

 

[TSny]

You are welcome.