How is it that substances can have the same chemical formulas but make different types of matter?

What would we observe on earth if the sun's internal energy source suddenly shut off?

A railway wagon of mass 20t is moving along a level track at 10km/h when it collides and couples together with a second wagon of mass 25t moving in the same direction at 5km/h.

A mover brings a box up the stairs in 10 seconds. If he applied a force of 20 N over a distance 10 m on the box, calculate the power required for him to complete this action. 0.05 watts 201 watts 2,000 watts 20 watts

Which of the following is NOT a way that machines provide a mechanical advantage? a. change direction b. change distance c. change power d. change force

What causes a tsunami to grow taller as it reaches the shore?

How can we describe an atom

What is the volume of a gold nugget that weight 2.20kg. the density of gold is 19g/cm^3 ... ?

Explain how newton's first law of motion can be considered to be a consequence of newton's second law.

Propose a hypothesis for how the position of the ball will affect the amount of its gravitational pull energy

A water-skier is pulled behind a boat by a rope that is at an angle of 13° and has a tension of 490 N. The water-skier has a mass of 49 kg. Draw a free-body diagram showing the forces acting on the skier. (She is being pulled to the right.)