Positive - Friction allows us to create heat in a desperate situation, like being lost in the woods. If we didn't have friction, we would probably freeze to death.
Negative - Friction can also cause unwanted fires, such as forest fires. If friction didn't exist, we wouldn't have these.
Here's the part you need to know:
(Weight of anything) =
(the thing's mass)
times
(acceleration of gravity in the place where the thing is) .
Weight = (mass ) x (gravity) .
That's always true everywhere.
You should memorize it.
For the astronaut on Saturn . . .
Weight = (mass ) x (gravity) .
Weight = (68 kg) x (10.44 m/s²)
= 709.92 newtons .
__________________________________
On Earth, gravity is only 9.8 m/s².
So as long as the astronaut is on Earth, his weight is only
(68 kg) x (9.8 m/s²)
= 666.4 newtons .
Notice that his mass is his mass ... it doesn't change
no matter where he goes.
But his weight changes in different places, because
it depends on the gravity in each place.
When precipitation hits the ground and hydrosphere
You should have the velocity as a function of time either given explicitly or implicitly (a graph)
v = ds/dt (differentiating the position vector)
integrating the acceleration.
you can use impulse or work and energy principle and also newton law of motion to find acceleration then velocity
NOT SURE IF THAT WHAT YOU WANT.
