You throw a rock straight up from the edge of a cliff. It leaves your hand at time t = 0 moving at 13.0 m/s. Air resistance can be neglected. Find both times at which the rock is 4.00 m above where it left your hand. Enter your answers in ascending order separated by a comma. Express your answer in seconds.

What is a frequency of a wavelength

Two identical small charged spheres are a certain distance apart, and each one initially experiences an electrostatic force of magnitude f due to the other. with time, charge gradually leaks off of both spheres. when each of the spheres has lost half its initial charge, the magnitude of the electrostatic force will be

If an inclined plane is 5 m long and 2 m high, what is its mechanical advantage? a. 2.5 b. 3 c. 7 d. 10