Lab: Trajectories

Lab: Trajectories

Purpose:
To use your understanding of projectile motion to predict the impact point of a ball on
an inclined board.

Materials: Aluminum “v-channel”, steel ball, board, ring stand, clamp, paper, carbon paper

Experiment:
1. Set up the apparatus as shown.

2. Launch the ball from a readily identifiable and repeatable point near the top of the inclined ramp.
3. Tape a piece of carbon paper to the floor around where the ball landed. Launch the ball five times from the same place as before and verify that the ball lands in virtually the same place each time.

4. Determine the height of the bottom of the ball when it launches, and how far out from the table’s edge it lands.
5. Determine the launch speed of the ball from your measurements.

6.Place a board such that it touches the end of the lab table and the floor. Put a heavy mass on the floor at the foot of the board and use duct tape to fix the mass in place. Make appropriate measurements to determine the angle of the board. Determine the distance that the ball will travel.

7. Attach a piece of carbon paper to your board such that it “surrounds” the spot where you expect your ball to land.  Then run the experiment, launching your ball five times from the same spot.

8. Determine the experimental value of your landing distances d and report your experimental value as d ± σd.

Results:
The distance measured is 0.51+/-0.02m. The distance calculated is 0.53m.

Sources of uncertainty or error:
1.The board slide down a little when attached to the weight.
2.The channel have friction, so the velocity calculated will be larger than actual velocity.

Conclusion:
Based on the height and distance of the projectile motion, we can predict the impact point of a ball on an inclined board.