Final answer:
To achieve constant speed motion, the janitor must push downward with a force of 10.78 N along the handle of the broom.
Step-by-step explanation:
To determine the force with which the janitor pushes downward to achieve constant speed motion, we need to analyze the forces acting on the broom.
First, let's draw a free-body diagram for the broom. The vertical component of the janitor's force is equal to the gravitational force acting on the broom, which is given by:
Fvertical = m * g = 1.1 kg * 9.8 m/s² = 10.78 N
The horizontal component of the janitor's force is what overcomes the friction force. The friction force is given by:
Ffriction = μN = 0.45 * (m * g) = 0.45 * (1.1 kg * 9.8 m/s²) = 4.882 N
Since the broom is moving at a constant speed, the horizontal component of the janitor's force must be equal to the friction force:
Fhorizontal = Ffriction = 4.882 N
Therefore, the force with which the janitor pushes downward (along the handle of the broom) to achieve constant speed motion is 10.78 N.