Answer:
The work done by the weightlifter is equal to the force applied multiplied by the distance lifted. The force required to lift the weight is equal to its weight (mass x gravity), which is:
F = 210 kg x 9.8 m/s² = 2058 N
The work done is:
W = F x d = 2058 N x 1.5 m = 3087 J
Therefore, the weightlifter needs to apply a force of 2058 N and do 3087 J of work to lift the weight 1.5 m straight up into the air.