If two large objects are electrically attracted to each other, a) both objects must be negatively charged. b) both objects must be positively charged. c) one object must be negatively charged, and the other object must be positively charged. d) none of the above statements are absolutely true.

Determine the amount of work done when a crane lifts a 100-n block form 2m above the ground to 6m above the ground

Athermometer is removed from a room where the temperature is 70° f and is taken outside, where the air temperature is 10° f. after one-half minute the thermometer reads 60° f. what is the reading of the thermometer at t = 1 min? (round your answer to two decimal places.) ° f how long will it take for the thermometer to reach 30° f? (round your answer to two decimal places.)

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.