A source is producing 15 waves in 3.0s. The distance between a crest and a tough is 10.0 cm. Find:
(a) the frequency,
(b) the wavelength,
(c) the velocity of the wave.

What does si stand for,when referring to a system of measurement

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

1kg of water needs to recieve 4200j of energy to go from 90 degrees to 91 degrees. what is the specific heat capacity of water? what are the units?