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Theory:

In the previous section, we learned the basics of mass and weight. In this section, we will discuss apparent weight.
 
The weight you feel to possess during up and down motion is not the same as your actual weight.
The weight that the body acquires due to the action of gravity and other external forces acting on the body is called Apparent weight.
Let us see this from the following example:
 
Let us consider a person with mass '\(m\)' is travelling in a lift.
 
5(1).png
A person in a moving lift
  
The actual weight of the person is \(W\ =\ mg\), which acts vertically downwards.
 
The reaction force exerted by the surface of the lift '\(R\)', considered as apparent weight, acts vertically upwards.
 
Let us see different probabilities of the apparent weight '\(R\)' of the person that arises, based on the movements of the lift, upwards or downwards, which are given in the below table.
 
Position of the lift
Case 1: Lift is moving upward with an acceleration '\(a\)'
Case 2: Lift is moving downward with an acceleration '\(a\)'
Case 3: Lift is at rest
Case 4: Lift is falling down
freely
Reaction force (\(R\))
R  W = Fnet = maR = W + maR = mg + maR = m(g+a)W – R = Fnet = maR = W − maR = mg − maR = m(ga)Here,Acceleration(a)=0R = WR = mgHere,Acceleration(a)=gR=WmaR=mgmaR=mgmgR = 0
Comparison of '\(R\)' with '\(W\)'
\(R\ >\ W\)
\(R\ <\ W\)
\(R\ =\ W\)
\(R\ =\ 0\)
Remarks
Apparent weight
is greater than the
actual weight
Apparent weight
is lesser than the
actual weight.
Apparent weight is equal
to
the actual weight.
Apparent weight is equal
to zero.