Final answer:
The statement that gravity has a negative direction is true in a standard coordinate system where down is considered negative; for instance, gravity near Earth's surface is often represented as -9.8 m/s². The normal force, however, does not act in the direction of gravity but rather opposes it. It is true that a negative acceleration vector points in the opposite direction to that of a positive acceleration vector.
Step-by-step explanation:
Regarding the question whether gravity pulls down with a negative direction, it is important to remember that the sign (positive or negative) associated with gravity, or any force, is dependent on the chosen coordinate system. In many cases, especially in physics and math problems, the downward direction is chosen to be negative, which means gravity can have a negative value. For example, the acceleration due to gravity near Earth's surface is usually represented as g = -9.8 m/s² where the negative sign indicates that gravity is acting downward.
As for your questions:
- The statement that the normal reaction is the force that opposes the force of gravity and acts in the direction of the force of gravity is False. The normal reaction actually acts in the opposite direction of the force of gravity.
- It is True that the vector for a negative acceleration points in the opposite direction when compared to the vector for a positive acceleration.
When solving problems, it's essential to represent weight as a vector because it has both magnitude and direction. For objects on Earth, weight is typically considered a downward force.