a hockey puck is sliding across frictionless ice at 6m/s. a)what is the net force on the puck? b)what forces act on the puck?
a) net force is zero,
b) gravity and nornal force
To determine the net force on the hockey puck and identify the forces acting on it, we need to analyze the forces involved.
a) What is the net force on the puck?
Since the ice is frictionless, there is no force opposing the motion of the puck. Therefore, the net force on the puck is zero (0 N) when moving at a constant velocity.
b) What forces act on the puck?
Although the net force is zero, there are still two forces acting on the puck:
1. Gravity (Weight): The force of gravity acts vertically downward on the puck. The magnitude of this force depends on the mass of the puck. However, since we don't have the mass, we can assume that it is negligible for this specific situation.
2. Normal Force: The normal force is the force exerted perpendicular to the surface by the ice on the puck. It counteracts the force of gravity and ensures that the puck does not sink through the ice. Since the puck is not accelerating vertically, the normal force is equal in magnitude but opposite in direction to the force of gravity. Again, without the mass of the puck, we cannot determine the exact numerical value of the normal force. However, we know it balances out the force of gravity.
Therefore, in this scenario, the only relevant force is the force of gravity, countered by the normal force, but the net force is zero.
To determine the net force and the forces acting on the hockey puck, we need to understand Newton's second law of motion, which states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration.
a) To find the net force on the puck, we need to know its mass and acceleration. From the information given, we only have the velocity (6 m/s) but not the acceleration. However, since the puck is sliding on frictionless ice, we can assume that there are no external forces acting on it, such as friction or air resistance.
Without any external forces, the net force acting on the puck would be zero, according to Newton's first law of motion (law of inertia). Inertia states that an object will continue moving at a constant velocity if no external forces are applied. Therefore, in this case, the net force on the puck is zero.
b) The only force acting on the puck is the force of gravity. Gravity pulls all objects towards the center of the Earth. However, in this scenario, since the puck is sliding on frictionless ice, the force of gravity does not affect its horizontal motion. The only forces acting on the puck are in the vertical direction, due to gravity.
To summarize:
a) The net force on the puck is zero.
b) The only force acting on the puck is the force of gravity, which is acting vertically downward.