If a 150 pound man walks onto an elevator. Suddenly it rises rapidly from the 1st to 14th floor. if the man steps onto a scale in the elevator during the rapid rise, he would weigh...
A) 150 pounds
B) More than 150 pounds
C) Less than 150 pounds
Please explain, thank you.
Ftotal on man = m a
Force F up on man from scale, mg down on man
F - mg = ma
so
F = m g + m a
if a is + up then F bigger from scale
To determine how much the man would weigh on the scale in the elevator during the rapid rise, we need to consider the concept of apparent weight and the effects of acceleration.
When an elevator accelerates upward, there are two forces acting on the man: his actual weight (which is 150 pounds) and the force exerted by the floor of the elevator pushing upward (which is equal to the man's apparent weight).
According to Newton's second law, the net force acting on an object is equal to its mass multiplied by its acceleration (F = ma). In this case, the net force on the man is the sum of his actual weight and the force exerted by the floor of the elevator.
During the rapid rise, the elevator experiences an upward acceleration. Consequently, the force exerted by the floor of the elevator must be greater than the man's actual weight in order to create a net upward force. This means that the man's apparent weight will be more than his actual weight.
Therefore, the correct answer is:
B) More than 150 pounds