Two Dimensional Motion

What is Projectile Motion?

Projectile Motion is the general motion of objects moving through the air in two dimensions near the Earth's surface.

What is important to remember for the velocities of projectile problems?

The initial velocity is considered to be the moment AFTER the object is projected and the final velocity is to be the moment BEFORE it hits something.

What can be assumed for the acceleration in a projectile problem?

The acceleration is both CONSTANT and the gravitational acceleration that is 9.81 m/s^2.

How can projectile motion be found?

Using its horizontal and vertical components of the motion separately.

What is the velocity compared to the path?

The velocity is always TANGENT to the path.

What equations can be applied to the components of the projectile motion?

After separating the x component from the y component, then KINEMATIC equations can be used separately.

What can be deducted from the vertical component for velocity?

The initial velocity can be considered 0 so v(initial)=0.
The initial time is also 0. So v1=0 and t1=0.

What kinematics equation can be used to find time and the distance?

y=1/2gt^2

What can be deducted from the horizontal compponent?

There is no acceleration (no air resistance)
The horizontal velocity remains constant.

What kinematics equation can be used to find time and distance?

x=vt (d=rt)

How can the velocity at any time be found?

Vectorally! Use the x and y components to find the tangential velocity.

What interesting prediction did Galileo make for projectile motion?

That if an object is dropped at the same time as that object is projected, they will both reach the ground at the same time.

What are some general kinematic equations for constant acceleration?

v(x)=v(x0) + a(x) t v(y)=v(y0) + a(y) t
x=x(0)+v(x0) t+1/2 a(x) t^2 ==>Same just x=y
v(x)^2=v(x0)^2+2a(x) (x-x(0))=>Same just x=y

What is a modified equations for initial velocity?

v(x0)=v(0)cos(thata) and v(y0)=v(0)sin(thata)

Tips for when approching projectile problems

1. Read carefully and choose object to analyze
2. Draw a diagram demonstrating what is happening to the object
3. Choose the origin and an xy coordinate system
4. Select the same time interval for both the x and y components
5. Examine the horizontal and