Posted by anoynomous on .
a weightlifter raises a 200kg barbell with an acceleration of 3 m/s. How much force does the weightlifter use to raise the barb?

science 
MathMate,
To maintain the weight at the same place, the force required is mg.
To accelerate upwards at acceleration a=3m/s², he/she must apply an additional force of ma.
So the total force is
m(g+a) N
where
m=mass of weight
g=acceleration due to gravity
a=acceleration upwards. 
science 
Anonymous,
400kg

science 
tyree,
A weightlifter raises a 200kg barbell through a height of 2 m in 2.2 s. The average power he develops during the lift is