The direction of straight up is called "vertical."
light travels in straight paths called rays
A straight line that represents a light wave is called a ray. It is used to show the direction of light propagation in geometrical optics.
The phenomenon where light waves travel in straight lines is called rectilinear propagation. This means that light travels in a straight path unless it encounters a medium that causes it to change direction.
gravity (up to down) friction
The distance and direction of an object from the starting point is called displacement. Displacement is a vector quantity that represents the straight line distance between the initial and final position of an object, along with the direction from the starting point to the endpoint.
I have no idea
The forces acting in a vertical direction or in a straight direction is called vertical force
a road......?
Stand straight. Now point straight up. Point straight ahead. Point straight to your left. Now point in a direction at right angles with all three previous directions: there's your extra dimension.
Displacement.
It is called a line segement
it is called a ray
Vertical means straight up and down,aligned with the direction of gravity. Vertically upward means vertical in the up direction. So if you jump directly straight up that is vertically upward; when you land you are travelling vertically downward.
light travels in straight paths called rays
A straight line that represents a light wave is called a ray. It is used to show the direction of light propagation in geometrical optics.
The phenomenon where light waves travel in straight lines is called rectilinear propagation. This means that light travels in a straight path unless it encounters a medium that causes it to change direction.
Without more specific information as to the direction of the turn: * Straight up * Straight down * West * East.