Weight- force of gravity on it. measured in newtons.
Mass- quantity of matter inside an object. measured in Kg.
- 1KG = 10N
- force of gravity on a 1KG object: GRAVITATIONAL FIELD STRENGTH (N/kg) if we know the mass, we can calculate the weight:
WEIGHT= MASS x GRAVITATIONAL FIELD STRENGTH
GFS is always 10 so -->
1) calcuate the weight in N of a person of mass 55Kg= 55 x 10= 550N
W = mg
w= weight in newtons (N)
m= mass in kg
g = GFS (n/kg)
if an object falls with NO OTHER forces acting on it, the resultant force (N) = (mass x acc.) will be its weight. - because this is what is making it accelerate downwards.
It will then accelerate constantly down at 10m/s squared. = ACCELERATION DUE TO GRAVITY.
eg 1 kg object above the ground: the force of gravity is 10N (coz 1kg=10N) and so its acceleration ( by re-arranging the equation we get force/mass= 10N/1KG)= 10m/s squared.
Objects falling through fluids- objects falling through air, liquid
Drag Force- a force opposing the motion of an object as it goes through a fluid such as air or liquid (the force that makes it go up)
- increases with speed
- so the resultant force (overall force)…