Answer:
22.05J
Step-by-step explanation:
When we lift a 3 kg mass a distance of 0.75m, the change in potential energy is calculated as
PE = mgh
PE = (3 kg)(9.8 m/s²)(0.75 m)
PE = 22.05 J
Then, the work needed to lift the 3 kg is equal to the potential energy, so
W = mgh
W = 22.05 J
Therefore, the answer is 22.05J