physics

 1) Explain why an object too far from the motion detector will produce an incorrect distance reading?

2) Look up an approximate value for the speed in air (at temperature of 20 C degrees) for 49 kHz ultrasound.[HINTL ultrasound is still sound, so searching for the velocities of the sound of different frequencies may be helpful.] Record your value in m/s and give the source of your information.

3) Estimate the dead time of the ultrasonic detector after emitting a pulse. Show your work

4) Explain why only consider one-dimensional motion when using a single motion detector. Based on the definition of velocity, describe what you should observe in the velocity vs. time graph if you were measuring a stationary, distant object and you suddenly slid an object into the beam from slide.[Hint: Think about the behavior of the position graph in this case.]