By counting the number of waves that pass a certain point each second, we will know the of the wave.
a. frequency
b. wavelength
c. speed
d. source

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

When can a theory be modified if a new type of technology allows for new observations that raise new questions? a-immediately, while the questions about the theory are being asked b-after new hypotheses related to the theory are tested in experiments c-only after the new observations disprove all parts of the theory d-while scientists begin to think about how the theory could improve

Dc versus ac problem. suppose your dc power supply is set to 15 v and the vertical setting on the oscilloscope is at 5 v/div. how many divisions will the trace deflect if you connect the output of the power supply to the scope with the a input switch set on dc? how many divisions if the switch is on ac?