A Carnot engine takes 3000 J from a reservoir at 600 K, does some work, and discards some heat to a reservoir at 300 K. What is its efficiency?

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The two stars in a certain binary star system move in circular orbits. The first star, Alpha, has an orbital speed of 36 km/s. The second star, Beta, has an orbital speed of 12 km/s. The orbital period is 137 d.

A circular radar antenna on a Coast Guard ship has a diameter of 2.10 m and radiates at a frequency of 11.0 GHz. Two small boats are located 8.00 km away from the ship. How close together could the boats be and still be detected as two objects

Why is recycling a way of reducing pollution

While painting the top of an antenna 275 m in height, a worker accidentally lets a 1.00 L water bottle fall from his lunchbox. The bottle lands in some bushes at ground level and does not break.

Chandra is doing an experiment to find out which type of dog food her dog prefers. The following are the steps of her experiment: 1. Place five identical bowls next to each other in the dog's yard. 2.

A teacher has asked four students to state a scientific theory. Which student is correct?

What are the two main currents that affect the US on the east and west coast?

What role do volcanoes play in the flow of energy and cycling of matter on earth?

How does uniform linear motion differ from uniform circular motion?

A metal underground water pipe that is in direct contact with the Earth for? or more is a code-recognized as a grounding electrode and must be included in the grounding electrode system.