Horizontal Projectile Motion Review

 

Anything that travels through the air without guiding its flight is a projectile. Examples include a spear, arrow,bullet, cannonball, model rocket, baseball, football, skydiver. Non-projectiles are parachutes, airplanes, helicopters, gliders, birds when flying. Air resistance is a factor in a projectile's flight. However, at this level of physics, air resistance, also called "drag," will always be ignored.

Projectile motion problems are kinematics problems in 2 dimensions.

When solving projectile motion problems always:

  • Be clear in your solution and use lots of space on your paper. Conserving paper will cost you points because it makes for poor communication. Plan on using a page for each problem's solution.
  • Draw and label a picture
  • List the given in a clear table
  • Show your requations
  • If needed, insert an equation into another equation before replacing variables with numbers and units, (like in example 1 below.)

 

Example 1
In a crazy stunt for the television show, America’s Got Talent, a woman places a large cannon on top of a building 22.0 m above the ground. When the woman is shot horizontally out of the cannon she will land 15.0 m along the ground from the front of the cannon. How fast was she moving when she left the cannon?

This is what should appear on your paper.

  • Drawing with measurements
  • "Givens" table.
  • Equations with variables only.
  • Equations substatuted into other equations.
  • Numbers and units
  • Answer with units.

This video can be found on YouTube at https://youtu.be/HCtBnlfJUTQ

 
Example 2
A toy car rolls horizontally off a table that is 1.00 m above the floor at 2.00 m/s. The car lands 0.9035 m from the edge of the table, along the floor. How much time did the toy car spend in the air?

This is what should appear on your paper.

  • Drawing with measurements
  • "Givens" table.
  • Equations with variables only.
  • Equations substatuted into other equations.
  • Numbers and units
  • Answer with units.

You can also solve this problem using only the verical givens. You will get the same answer. The video shows how to do this.

 

This video can also be found on YouTube at https://youtu.be/C96buly5OE8

 
Example 3
A basketball rolls horizontally off a high bleacher at 2.00 m/s. It takes exactly 2 seconds to land on the ground. How far away, horizontally, did it travel before landing on the floor?

This is what should appear on your paper.

  • Drawing with measurements
  • "Givens" table.
  • Equations with variables only.
  • Equations substatuted into other equations.
  • Numbers and units
  • Answer with units.

 
Example 4
Tim runs horizontally off a ledge at 5.00 m/s into a pond. He lands 3.00 m away from the edge. How high was the ledge Tim jumped from?

This is what should appear on your paper.

  • Drawing with measurements
  • "Givens" table.
  • Equations with variables only.
  • Equations substatuted into other equations.
  • Numbers and units
  • Answer with units.

 

by Tony Wayne ...(If you are a teacher, please feel free to use these resources in your teaching.)