Answer :
weight=mass*gravitational accelaration
we know the weight and the gravitational acceleration
400N=m*10m/s^2
m=400N/10m/2^2
m=40kg
weight=mass*gravitational accelaration
we know the weight and the gravitational acceleration
400N=m*10m/s^2
m=400N/10m/2^2
m=40kg