Determine to three significant figures the gravitational force acting between two spheres that are touching each other. The mass of each sphere is 900kg and the radius is 200mm .

Question

anonymous · Answer

I converted 200 mm into meters so m=0.200

I did the equation and got an answer of 0.00135128 N however that is wrong. Should I use scientific notation even though it asks for 3 sig figs?

anonymous · Answer

3 significant figures from the value 0.00135128   would be  .00135

anonymous · Answer

$$F=G \frac{ 900*900 }{ .2^{2} }$$ Where G= 6.673*10^-11

anonymous · Answer

I entered 0.00135 and it was wrong...

anonymous · Answer

oh ok so it would  1.35 x10^-3   work?

anonymous · Answer

No its not the right answer. I did it multiple times and the answer is wrong...

anonymous · Answer

hmm... sorry I cna't help you with the formula part since I havnet' done that yet :(   but i think you might be missing something in your calculation maybe?

anonymous · Answer

I don't think so. I did the formula several times and even checked with an online calculator.

anonymous · Answer

hmm.. try multiplying the radius x2   .... if each sphere both have 200 mm radius the distance should be their radius added together right?

anonymous · Answer

.000339

anonymous · Answer

Yeah I just realized that. Thanks for the help!