In: Physics
An object is placed on the floor of an elevator. Which of the following statements is correct regarding the magnitude of the normal force that the elevator floor exerts on the object?
A) It is always the same as the weight of the object regardless
the state of motion of the elevator
B) It is less than the weight of the object if the elevator moves
downward with a constant velocity
C) It is largest if the elevator undergoes free fall
D) It is less than the weight of the object if the elevator moves
upward with an acceleration
E) It is the same as the weight of the object if the elevator is
moving with a constant speed
here,
when An object is placed on the floor of an elevator,
the magnitude of the normal force that the elevator floor exerts on the object , N = m* g + m * a
where a is the acceleration of lift
when it is moving at constant velocity in either direction
acceleration is zero and normal force is equal to the weight of object
when the lift is accelerating upwards
the normal force , N = m * ( g + a)
so, the normal force is greater than weight
when the lift is accelerating downwards
the normal force , N = m * ( g - a)
so, the normal force is less than weight
the correct option is ( E) It is the same as the weight of the object if the elevator is moving with a constant speed)