You jump into a swimming pool on a day when the air temperature is 100°F and the water is 80°F. Which statement correctly describes the flow of heat? A.
Heat flows from the water to your body.
B.
Heat flows from the water to the air.
C.
Heat flows from your body to the water.
D.
Heat flows from your body to the air.

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

What would be the strength of earth's gravitational field at a point where an 80.0 kg astronaut would experience a 80% reduction in weight