An EF 151 GTA sits on the EF stool and rotates CCW with an initial speed of 60 rpm. After 28 revolutions he stops. Assuming constant acceleration, how long was he rotating?

Answer 1

Before there was central heating, hot water bottles were used to keep people warm at night. These flat containers were filled with hot water and placed at the foot of the bed, under the blankets. How was the heat energy transferred from the hot water bottle into the space under the blankets?

Answer 2

convection

Answer 3

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