How do plants break rocks into smaller pieces

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

You have a resistor and a capacitor of unknown values. first, you charge the capacitor and discharge it through the resistor. by monitoring the capacitor voltage on an oscilloscope, you see that the voltage decays to half its initial value in 2.70 miss . you then use the resistor and capacitor to make a low-pass filter. what is the crossover frequency fc?

How does a circuit breaker protect a refrigerator? a. when the current is too high, a metal strip in the fuse melts and opens the circuit. b. when the resistance is too high , a re-settable which opens a circuit c. when the current is too high , a re-settable switch opens the circuit d. when the resistance is too high a metal strip in the fuse melts and opens the circuit