A 7.50 kg stone is rubbed across the ceiling of a cave by a force F angled upward. If the coefficient of kinetic friction is .72 and the angle of the force with the horizontal ceiling is theta equals 65 degrees, what is the magnitude of the force F if the stone is pushed with constant velocity

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?