Trevor skis down a hill at a speed of 25 m/s. Friction slows him down to a speed of 20 m/s. Which free-body diagram shows the forces acting on him
ftiction up the hill, gravity force straight down,
To determine the forces acting on Trevor as he skis down the hill, we need to analyze the situation from a free-body diagram perspective. A free-body diagram is a visual representation of the forces acting on an object.
In this case, as Trevor skis down the hill, there are two main forces at play: gravity and friction.
1. Gravity: The force of gravity, represented by the vector Fg, always acts vertically downward toward the center of the Earth. Its magnitude can be calculated using the equation Fg = mg, where m represents Trevor's mass and g represents the acceleration due to gravity (approximately 9.8 m/s²). Therefore, the magnitude of Fg is given by Fg = m * 9.8 N.
2. Friction: The force of friction, represented by the vector Ff, acts in the opposite direction of motion and its magnitude depends on the coefficient of friction (μ) between the skis and the snow or ice. The magnitude of Ff can be calculated using the equation Ff = μ * N, where N represents the normal force acting perpendicular to the surface Trevor is skiing on.
Now, since we know that friction slows Trevor down from a speed of 25 m/s to 20 m/s, it means that the frictional force is acting in the opposite direction of his motion. Therefore, the free-body diagram should show the force of friction (Ff) directed upwards (+y direction) to oppose the motion, and the force of gravity (Fg) directed downwards (-y direction) as he skis down the hill.
Remember, it's important to include the proper labels on the diagram to indicate the nature and direction of each force (e.g., Ff, Fg).