2D Kinematics

Two dimensional kinematics uses both the x-axis and the y-axis. This is called working in two dimensions.

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Two dimensional kinematics use two different types of quantities, vectors and scalars.

• Vectors express direction along with values
• Scalars express only values.

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Two dimensional motion is also

Fig.1

measured using displacement which is the distance form the starting postion to the finish position. Vectors are measured using the tail to tip method which is where two vectors are drawn tip to tail the express the two different dimensions of motions. Then the resulting vector is drawn to where it connects the tail of one to the tip of the other. See Fig. 1.

• You can multiply and divide vectors and scalars, just remember to take into account the direction of the vector.
• Vectors can be broken up into different components, usually in the horizontal and vertical axises. This is done using trigonometry. When drawn the result is a force diagram. See Fig. 2.

Fig. 2

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There are also projectile motion problems in 2D kinematics.

• Vertical acceleration is going to be the same for all objects on Earth.
  • The objects can also have movement in the other dimension that does not affect the vertical movement.
• When an object is shot (as in a projectile problem) the horizontal component remains constant while the vertical component changes due to acceleration.
• Due to the existance of the Earth's gravity, the equation for the object's path will always be parabolic.

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Equations:
1.	vf^2=vi^2+2*a*(xf-xi)
2.	xf=xi+.5at
3.	yf=yi+vi*t-.5*a*t^2
4.	vf^2=vi^2-2*a*(xf-xi)

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Sites for additional reference:

Spark Notes

1D Kinematics