Home › Tamil Nadu SSLC (Class 10) › Physics › Laws of Motion › A lift moves downward with an acceleration a les…
A lift moves downward with an acceleration a less than g. The apparent weight of a person of mass m inside it is
AMore than the actual weight mg
BExactly equal to the actual weight mg
CLess than the actual weight mg
DAlways zero during the motion
Answer & Solution
Correct answer: C. Less than the actual weight mg
1. For downward acceleration, the net downward force is mg − R = ma.
2. So R = mg − ma = m(g − a).
3. Since a is positive, R is less than mg, so apparent weight is less than the actual weight.
4. Rule out zero: that occurs only in free fall when a equals g.
_Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 1 "Laws of Motion", p.18_
Related questions
A stone is whirled on a string. The inward force keeping it on its circle is the centripetA ring or sphere rolling without slipping touches the ground at just one point at a time. Experiments show that the coefficient for a sliding object compares with the one for a staThe constant of proportionality linking maximum static friction to the normal force is theThe friction acting before an object begins to slide is distinguished from the friction acA crate is pushed but does not budge. The surface force that cancels the push is called:A book lies still on a table. Balancing its weight is an upward push from the table calledTwo railway wagons collide and couple together. The standard application of conservation o