What are two quantities of an object launched parallel to the ground which are equal to zero?
I think one of the two is vertical velocity.
Horizontal acceleration.
You are correct! The vertical velocity of an object launched parallel to the ground is equal to zero at two specific points. However, there is another quantity that is also zero.
To find the two quantities that are equal to zero, we need to consider the motion of the object. When an object is launched parallel to the ground, it follows a projectile motion. In this motion, the object moves horizontally and vertically simultaneously.
The first quantity that is equal to zero is the vertical velocity (or sometimes referred to as the y-component of velocity). The vertical velocity represents the rate at which the object is moving up or down. When the object is at the highest point of its trajectory or at the very beginning when it is launched, the vertical velocity is zero.
The second quantity that is equal to zero is the vertical displacement (or sometimes referred to as the y-component of the position). The vertical displacement represents the change in height of the object with respect to a reference point. When the object is at the level it was launched or at the highest point of its trajectory, the vertical displacement is zero.
So, the two quantities of an object launched parallel to the ground that are equal to zero are the vertical velocity and the vertical displacement.