Question

Consider a person sliding down a water slide at constant velocity. What are the forces acting on the person as they slide? Determine if the forces are balanced or unbalanced. Explain.
A) Gravity and friction are acting on the person. The forces are unbalanced because the person is sliding down the slide.
B) Gravity and air resistance are acting on the person. The forces are balanced until the person reaches the bottom of the water slide.
C) Weight, gravity, and friction are acting on the person. The forces are unbalanced. Gravity is the strongest force causing the person to move.
D) Gravity and friction are acting on the person. The forces are balanced. There is no net force because the person is moving at a constant velocity.

Answer 1

Answer:

D) Gravity and friction are acting on the person. The forces are balanced. There is no net force because the person is moving at a constant velocity

Explanation:

Net Force

The first Newton's Law explains that a body keeps its velocity or at rest unless a net force is exerted on it. The second Newton's law gives us a mathematical expression for that net or unbalanced force as:

$F_n=m.a$

where m is the mass of the object and a its acceleration. Recall a body at constant velocity has zero acceleration.

The question describes how a person is sliding down a water slide at a constant velocity. That's all we need to know there is no net force acting on it. All the forces are balanced. The only possible options supporting this statement are B and D. We don't know if there is air resistance (B) or friction (D), but option B suggests the forces are balanced until the person reaches the bottom of the water slide. Option D is correct because the forces are balanced all the time