Which of the following is an example of convection?

the rays of the Sun warming the earth

a hot oven warming the air around it

a hot object transferring heat to a cooler one

hot air rising and cooler air falling

Which statement is true about the atoms in helium gas? A. They have strong attractions to one another. B. They are not closely packed. C. They are arranged in an orderly pattern. D. They travel in circular paths.

In which type of wave do air particles move together or apart parallel to the direction of the wave? A. transverse waves B. surface waves C. sound waves D. electromagnetic waves

One isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?

What is the 3d model of oxygen molecule

What is the fundamental property of matter that can either be positive or negative?

What happens to the resistance of a filament if it is replaced by a shorter wire?

One group of scientists feel that global warming affects the frequency of hurricanes. Another group of scientists believe that global warming does not affect the frequency of hurricanes, but it makes the average hurricane stronger.

In an experiment, all participants receive a treatment but those in the control group recieves a false treatments

When the volume increased, what happened to the density?

8. Chemical weathering occurs more rapidly in what kind of climates? A. Desertlike B. Cold with high snowfall amounts C. Cool and dry D. Warm with abundant rainfall