These supplies are needed:

ripple tank with dampers
high intensity light source
white paper
protractor
electrical wave generator
paraffin blocks
thick wooden dowel


Follow these directions and answer the questions.

1. Set up the ripple tank with its light source and white paper screen. Use approximately one-half inch of water and level the tank.

img/riptank1.gif

2. Set the reflecting barrier parallel to the generator (the dowel, in this case). Use the dowel to generate pulses.

In what direction do the reflected pulses move?

3. Use a protractor or architects angle to set the barrier 45o to the generator. Observe the pulses and the barrier by their shadows on the screen. Generate pulses and lay pencils or rulers on the screen parallel to the pulses.

How does the new orientation affect the direction of the reflected pulses?

4. Vary the orientation of the barrier between parallel to and perpendicular to the generator. For each orientation, compare the incident angle to the reflective angle. How do the incident and reflected angles compare?