For about how many years of geological time have the dinosaurs existed on Earth?

Understanding Relationships How can it be that Earth is at perihelion during wintertime in the Northern Hemisphere?

Why does atmospheric pressure decrease as you go higher in altitude on earth?

Describe the arrangement of the sun, the moon, and Earth during a solar eclipse and a lunar eclipse.

What upward gravitational force does a 5600 kilogram elephant exert on Earth?

Consider an object of mass $m$ orbiting the Earth at a radius $r$. Find the speed of the object.

Earth is gravitationally attracted to a. Mercury. b. the moon. c. the sun. d. All of the above

How would the seasons be different if Earth were not tilted on its axis? Explain.

One kg weighs $10$ N on Earth. Would it weigh more or less on the Moon?

If the temperature of the earth warms up how does the carbon dioxide cycle respond?

How far from Earth's center is the center of mass of the Earth Moon system?

Almost all of the oxygen on the planet Earth is found in the atmosphere. Is this statement true or false?

The orbital revolution of the Moon about Earth takes about 27.3 days and is in the same direction as Earth's rotation (24 h). Use this information to show that high tides occur everywhere on Earth every 12 h and 26 min.

Considering that millions of species have lived on Earth, why are there relatively few fossils?