a solid cubic centimeter of platinum weighs 21.5 N. if this cube of platinum is placed under water, what volume of water is displaced? what weight of water is displaced? (Hints: 1 cm3 of water has a mass of 1 gram; 1 gram weighs 0.0098 N; density of platinum = 21.5 g/cm3.)

Modify the equation fδt=δ (mv) to find the force of friction.

Copper has free electrons per cubic meter. a 71.0-cm length of 12-gauge copper wire that is 2.05 mm in diameter carries 4.85 a of current. (a) how much time does it take for an electron to travel the length of the wire? (b) repeat part (a) for 6-gauge copper wire (diameter 4.12 mm) of the same length that carries the same current. (c) generally speaking, how does changing the diameter of a wire that carries a given amount of current affect the drift velocity of the electrons in the wire?

How is coal extracted from mountaintop removal mines? a. dynamite is used to create underground tunnels where miners go to extract the coal. b. dynamite is used to break apart rocks and then draglines are used to remove the broken rock and reach the coal. c. coal in mountaintops is extracted by digging strips in the landscape to reach the coal. d. placer deposits in mountain river bottoms are removed by