Answer:
(a) the student's apparent weight during the lift is 914.2 N
(b) the student's apparent weight during the fall is 0
Step-by-step explanation:
Given;
student weight, W = 700 N
upward acceleration, a = 3 m/s²
Apply Newton's second law of motion;
The reading on the scale = student's apparent weight
(a) during the lift
R = W + F
R = W + ma
where;
m is mass of the student = 700 / 9.8 = 71.4 kg
R = 700 + 71.4(3)
R = 700 + 214.2 N
R = 914.2 N
(b) during the fall
R = W - ma
R = mg - ma
R = m(g-a)
here, a = g
R = m(g - g)
R = m(0)
R = 0
Thus, during the free fall the student experiences weightlessness or zero apparent weight.