The power required to lift a mass of 8·0 kg up a vertical distance of 4 m in 2 s is (taking acceleration due to gravity as 10 m/s²):
80 W
160 W
320 W
640 W
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC NDA-1 – 2023
– Work done (W) = Force × distance (W = Fd).
– Power (P) = Work done / Time (P = W/t).
Force required to lift the mass = W = mg = 8.0 kg × 10 m/s² = 80 N.
Work done = Fd = 80 N × 4 m = 320 Joules.
Power = Work done / Time = 320 J / 2 s = 160 Watts.