Observation #4 Two Dimension Relative Motion – Launching a Projectile

In order to demonstrate 2D (two dimensional) relative motion, a 2D checkbox were added.

Refresh the web page again.

Part A) Click the right mouse button to suspend the animation. Click the 2D checkbox. Place the mouse cursor on the ground and click the right mouse button to resume the animation. Notice a ball will be thrown upward from the barge moving in the river. Your frame of reference is the ground.

The trajectory of the ball (blue) will be shown to you from the frame of reference of the ground.

Describe the trajectory of the ball seen on the screen. _____________________________

Where does the ball land when it falls? _________________________________________

Does the ball have motion in two dimension (vertical and horizontal)? ________________

What do you observe to be the velocity of the barge? ______________________________

What do you observe and conclude the horizontal velocity of the ball must be? __________

Part B. Refresh the webpage again.

Click the right mouse button to suspend the animation. Click the 2D checkbox. Place the mouse cursor on the Riverand click the right mouse button to resume the animation. Your frame of reference is now the river.

The trajectory of the ball (blue) will be shown to you from the frame of reference of the river.

Describe the trajectory of the ball seen on the screen. _____________________________

Where does the ball land when it falls? _________________________________________

Does the ball have motion in two dimension (vertical and horizontal)? ________________

What do you observe to be the velocity of the barge? ______________________________

What do you observe and conclude the horizontal velocity of the ball must be? __________

Part C. Refresh the web page again.

Click the right mouse button to suspend the animation. Click the 2D checkbox. Place the mouse cursor on the boat and click the right mouse button to resume the animation. Notice a ball will be thrown upward from the barge moving in the river. Your frame of reference is the boat.

The trajectory of the ball (blue) will be shown to you from the frame of reference of the ground.

Describe the trajectory of the ball seen on the screen. _____________________________

Where does the ball land when it falls? _________________________________________

Does the ball have motion in two dimension (vertical and horizontal)? ________________

What do you observe to be the velocity of the barge? ______________________________

What do you observe and conclude the horizontal velocity of the ball must be? __________

Summarize the Main Ideas you learned in this virtual lab regarding how the description of motion depends on the frame of reference.