A bag of sugar has a mass of 7.86 kg. a. What is its weight in newtons on the moon, where the acceleration due to gravity is one-sixth that on earth? b. What is its weight on Jupiter, where the acceleration due to gravity is 2.64 times that on earth?

2 Answers

The bag weighs 77.0 N on Earth, 12.84 N on the Moon and 203.35 N on Jupiter.

Explanation:

Whenever we are asked to determine the weight of an object based on its mass, the relation is

#W=mxxg#

where #W# is the weight and #g# is the acceleration due to gravity in the location where the mass #m# is found.

So, if #g# on the moon is #1/6# of the value of #g# on Earth (which is #9.8m/s^2#, the weight on the Moon is

#W= (1/6)(9.8)(7.86) = 12.84 N#

and on Jupiter

#W= (2.64)(7.86)(9.8) = 203.35 N#

By the way, it is also common to call #g# the strength of the gravitational field in a location. Its units are N/kg (notice how this ultimately simplifies to #m"/"s^2#), which ties in nicely with the question here.

Nov 8, 2017

#W_m=mg_m=7.86*1.635~~12.85N#
#W_j=mg_j=7.86*25.8984~~203.56N#

Explanation:

The equation for weight is #W=mg#, where:

  • #W# = Weight (#N#)
  • #m# = mass (#kg#)
  • #g# = acceleration due to gravity (#ms^(-2)#)

On Earth, #g=9.81ms^(-2)#

For the Moon, #g_m=g/6=1.635ms^(-2)#

For Jupiter, #g_j=2.64g=25.8984ms^(-2)#

#W_m=mg_m=7.86*1.635~~12.85N#
#W_j=mg_j=7.86*25.8984~~203.56N#