Forces in Elevator Moving at Constant Speed · PhysicsBowl 2011 #10

Physics · mechanics

Problem

A string of negligible mass connects an object of mass

m_0 = 10

kg to the ceiling of an elevator. The elevator experiences a constant downward speed of

3.0

m/s. Let

T_0

represent the magnitude of the force on the mass by the string (tension),

W

represent the magnitude of the gravitational force by the Earth acting on the mass hanging in the elevator, and

F_{net}

represent the magnitude of the net force acting on the mass

m_0

. Which one of the following choices describes the relationships between these forces? (A)

F_{net} > T_0 > W

(B)

F_{net} = W = T_0

(C)

F_{net} > W > T_0

(D)

F_{net} = T_0 > W

(E)

F_{net} > T_0 = W