8. What is the frequency of the standing wave shown?
a. 12 Hz
b. 24 Hz
c. 36 Hz
d. 48 Hz
9. What would be the fundamental (1st harmonic) frequency of the string?
a. 12 Hz
b. 24 Hz
c. 36 Hz
d. 48 Hz

When a neutral charge, comes into contact with a positive charge they repel each other nothing happens the neutral charge becomes negative they attract each other

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?

A10nc charge sits at a point in space where the magnitude of the electric field is 1500 n/c. what will the magnitude of the field be if the 10 nc charge is replaced by a 20 nc charge? assume the system is big enough to consider the charges as small test charges.