Final Answer:
A ball thrown directly upward has an initial velocity of B) Positive velocity.
Step-by-step explanation:
When a ball is thrown directly upward, the initial velocity is positive. This is because the motion is against the force of gravity, and the velocity vector is directed opposite to the gravitational pull. By convention, upward velocities are considered positive, and downward velocities are negative.
The magnitude of the initial velocity depends on the force applied during the throw. If the initial velocity is given as 0 v 0, it will be positive as it represents the speed and direction of the ball away from the Earth's surface. In contrast, if the ball were thrown downward, the initial velocity would be negative. The sign convention for velocities makes it easier to analyze and understand the motion of objects in the presence of gravitational forces.
Understanding the direction and magnitude of initial velocity is fundamental in physics, especially in kinematics. In the case of a ball thrown upward, the positive initial velocity indicates an upward motion against gravity. This distinction in velocity signs aids in correctly applying kinematic equations and predicting the behavior of the projectile throughout its trajectory."