Three beakers are of identical shape and size , one beaker is pained matt black, one is dull white and one is gloss white . The beakers are filled with boiling waterin which beaker does the water cool more quickly? Give reason. ( i really need the answer quickly)

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.

What is friction? how does it affect the motion of an object?

Acircuit contain a 5-ohm,a3-ohm,and an 8-ohm resistor in series. what is the total resistance of the circuit