A man of mass $60$ kg stands on a weighing scale in a lift accelerating upwards at $2$ m s$^{-2}$. What reading does the scale show? (Take $g = 10$ m s$^{-2}$.)

The scale reads the normal reaction $N$. From $N - mg = ma$: $N = m(g + a) = 60 \times 12 = 720$ N. A reading of 480 N would apply if the lift were accelerating downwards, and 600 N is the true weight, read only when the lift is not accelerating.