Pendulum takes 0.04 seconds to complete one oscillation. find its frequency

A248-g piece of copper is dropped into 390 ml of water at 22.6 °c. the final temperature of the water was measured as 39.9 °c. calculate the initial temperature of the piece of copper. assume that all heat transfer occurs between the copper and the water. remember, the density of water is 1.0 g/m

The mini-refrigerator fire was most likely caused by what type of wiring?

What is the role of lenses in microscopy?