- #1

joyxx

- 6

- 1

## Homework Statement

A) What is the weight (in Newtons) of an 80 kg person at the Earth's surface?

B) What is the weight of the same person on the surface of the planet with a mass 8.0 x 10^24 kg and a radius of 5.5 x 10^6 m? (G=6.67 x 10^-11 N*m^2/kg^2)

C) what is the apparent weight (scale reading) if the person stands on a Newton scale inside an elevator accelerating at 0.80 m/s^2 (up)?

## Homework Equations

F=ma

F=Gm1m2/r^2

## The Attempt at a Solution

A) F=ma

m=80 kg

a=9.8 m/s

F=(80 kg)(9.8m/s)

=784 N

B) F=Gm1m2/r^2

G=6.67 x 10^-11 N*m^2/kg^2

m1=80 kg

m2= 8.0 x 10^24 kg

r^2=5.5 x 10^6 m

F=(6.67 x 10^-11)(80)(8.0 x 10^24)/ (5.5 x 10^6)^2

F= 4.26 x 10^16/3.025 x 10^13

=1408.26 N

C) I can't figure out the formula for this one as my lesson doesn't give out much information

This course is being done online and it is very difficult to follow and the lessons don't give out detailed descriptions on how to do the questions, and the examples aren't very helpful.