Applications of Newton's Laws
Consequences of motion
Apparent weight and Newton's 2nd LawR = m(g + a)
Parameters
Mass60 kg
Acceleration magnitude3 m/s²
Elevator state
Results
True weight588.6 N
Apparent weight588.6 N
Difference0.0 N
Scale reads60.00 kg
Curriculum
WAECNECOIGCSESATJUPEB
š Teacher notes
- ā¢Apparent weight = R = m(g + a). When a > 0 (accelerating up), R > mg ā person feels heavier.
- ā¢When a < 0 (accelerating down), R < mg ā person feels lighter. When a = āg (free fall), R = 0.
- ā¢The scale reads apparent weight, not true weight. This is what WAEC/IGCSE questions actually ask for.
- ā¢Common exam trap: during constant speed (a=0), the person feels exactly their true weight regardless of how fast they're going.
- ā¢Deceleration at the top of an upward journey = acceleration downward ā lighter feeling, not heavier.
āļø Exercises