The parachutist has a mass of 75 kg. What is the weight of the parachutist?

3 Answers
Jul 11, 2017

#w = 740# #"N"#

Explanation:

Note: I would like to point out that if the parachutist is in free-fall, her apparent weight is zero. But her true weight--her gravitational attraction experienced from the earth--is as follows.

We're asked to find the weight of an object, with its mass known.

This is pretty straightforward, and we use the equation

#w = mg#

where

  • #w# is the magnitude of the weight, in newtons, #"N"#

  • #m# is the mass, in #"kg"# (given as #75# #"kg"#)

  • #g# is the acceleration due to gravity, #9.81# #"m/s"^2#

Plugging in known values, we have

#w = (75color(white)(l)"kg")(9.81color(white)(l)"m/s"^2) = color(red)(740("kg"•"m")/("s"^2)) = color(red)(740# #color(red)("N"#

rounded to #2# significant figures.

Jul 11, 2017

As long as she is in free fall, she's weightless.

Explanation:

Gravity will pull every mass down with a force of #F_g=g*m#
where #g# is the acceleration of gravity (#~~9.8m//s^2#).

Weight is the force that a mass may exert on a surface (or on a rope when hanging). When you're standing on a solid floor, gravity makes you push down on the floor, and if the floor is strong enough, it will push back with the same force you keep you in equilibrium.

While a parachutist is in real free fall, there is nothing to push or pull on, so she's weightless.

Jul 11, 2017

#735N#

Explanation:

I have a feeling we might be missing some information here, but if the parachutist is at rest on the surface of the earth, her weight is equal to the force of gravity acting upon her. Therefore, we have:

#W=F_g=mg#

#=(75kg)(9.8m/s^2)#

#=735N#

That might seem like an unreasonable answer at first, but hopefully it can serve to remind us that mass and weight are not the same quantity!