As water is heated by the sun, it becomes less dense and rises. What causes the decrease in the density of warming water?

22.0-kg child is riding a playground merry-go-round that is rotating at 40.0 rev/min. What centripetal force is exerted if he is 1.25 m from its center? (b) What centripetal force is exerted if the merry-go-round rotates at 3.00 rev/min and he is 8.

a rollercoaster car is moving 19.8 m/s on flat ground when it's hits the brakes. it decelerates at - 3.77 m/s^2 over the next 45.8 m. how much time does it take?

Is carbon transparent, translucent, or opaque?

What is the weight in pounds of a 7.0 kilogram bowling ball on earth surface

On top of Mount Everest, the temperature is - 19 ∘C in July. Being a physicist, you determine by how many degrees Celsius one needs to change the air temperature to double the average kinetic energy of its molecules.

Which of the following statements is true? A. Both chemical reaction rates and nuclear decay rates vary with the conditions of the reaction. B. Nuclear decay rates vary with the conditions of the reaction, but chemical reaction rates do not. C.

A star may form a black hole once it cannot?

Kai was 200 meters north of the library when he remembered he had to return some books to the library. It took him 200 seconds to do the round trip. Which best describes Kai's roundtrip?

The engine that powers a crane burns fuel at a temperature of 1500 oC. It is cooled by air at a temperature of 20 oC. The crane is used to lift a 1000 kg steel girder 30 m into the air.

The portion of a light ray that falls on a surface is a/an