Question

Will fan and medal!! David weighs 140 pounds on Earth. What is his weight on the Moon, which has one-sixth of Earth’s acceleration due to gravity? What does he weigh on Saturn, which has 28 times Earth’s acceleration due to gravity? Does his mass ever change? Is there a place where he would weigh less than 1 pound?

Answer 1

\[W = mg\]
\[W = Weight\]
\[M = Mass\]
\[G = Acceleration\]

I suggest finding the mass he is on Earth (Acceleration is 9.8 on Earth)

Once you find that multiply it by one-sixth the acceleration of Earth

\[W _{moon}= (m _{earth})(\frac{ 9.8 }{ 6 })\]
Then the same for Saturn:
\[W _{Saturn} = (m _{earth})((9.8)(28))\]

But first, find the Earth's mass of David

Answer 2

I agree with @FortyTheRapper and remember mass is a quantity that never changes only the weight as mass remains constant but weight is affected by the gravitational pull on different planets we weigh different but mass remains the same. :) and for your question where he would weigh less than 1 pound find out the mass by the equation
\[W=mg\]
where g=9.81 and weight is 140 so David's earth mass would be
\[m=14.27kg\]
so now for where he would weigh less than 1 pound lets set weight to 1N(newton)
\[1=14.27g\]
\[g=0.07m/s^2\]
so the place he would weigh less than 1 pound is the place where the gravitional pull would be less than 0.07 :)

Answer 3

So,

\[g < \frac{ 1 }{ m _{earth}}\]

Answer 4

you guys are great but encourage learning guys help with the formular then let the questionaire do the rest his/her self. that the good way to learn. if there is any problem he/she will ask for clarity. But kudos to you guys, you guys are awesome.

Answer 5

@FortyTheRapper @ijlal Thank you both SO much for walking me through this problem and explaining it in a way that I could understand. You're both awesome!!