20. The model of the universe that suggests that the sun is the center of the universe was first brought by

A. Copernicus.

B. Brahe.

C. Ptolemy.

D. Kepler.

If an object is accelerating, the forces acting on it must be ___.

Sand on a beach is covered by other layers of sand over time. The extra layers compress the first layer, packing it tighter and tighter. Over time, the bottom layers of sand have formed into sandstone, with colored bands showing the different layers.

The passengers in a roller coaster car feel 50% heavier than their true weight as the car goes through a dip with a 10 m radius of curvature. What is the car's speed at the bottom of the dip?

A 500 kilogram marlin and a 20 kilogram salmon are swimming at the same velocity. How does the momentum of the two fish compare? A. The marlin has more momentum. B. The salmon has more momentum. C. Both have the same momentum. D.

Electromagnetic waves with the lowest frequencies have the greatest amount of energy. True False

A ferris wheel takes 5 minutes to complete one full rotation, what is the angular velocity of the ferris wheel

A heat engine has a thermal efficiency of 45%. how much power does the engine produce when heat is transferred into it at a rate of 109 kj/hr?

Dos pelotas de tenis se lanzan verticalmente, hacia arriba y desde el mismo punto, con 2 s de diferencia. La velocidad inicial de la primera es de 20 m/s, y la de la segunda, de 30 m/s.

What is the primary function of the small intestines

A nuclear power plant generates a total of 150mw of power and 45% of this power is wasted heat that is discharged on the cooling water of a river. the river flows at 660.43 gal/s and has an upstream temperature of 64.4 ⁰f.