Most street lights are made from one or two elements mercury or sodium. Explain why astronomers preferred that cities you sodium streetlights instead of mercury streetlights

When you step on the accelerator to increase the speed of your car, the force that accelerates the car is: A. the force of your foot on the accelerator B. the force of friction of the road on the tires C. the force of the engine on the drive shaft D.

How does the magnetic force vary with distance?

A sleigh weighing 2000 newtons is pulled my a horse a distance of 1.0 kilometer (or 1000 meters) in 45 minutes. what is the power if the horse?

Some molecular compounds, such as HCl, ionize completely in solution. Some molecular compounds such as HC2H3O2 do not ionize completely when they dissolve in water. Which explains their solution properties?

Why would the discovery of a fossil imply that earth is much older than originally though?

A book falls of the table and hits the floor. Is work done? Why?

A person of 83 kg is in an elevator. If the elevator is moving at a speed of 5 m/s, what's the person's kinetic energy? Keep 4 significant figures a 1,004 J b 1,038 c 1,280 J d 980 J e 1,435 J

What two equations can be used to determine the speed of a wave

Which force has an infinite range and is always attractive?

A ramp with a mechanical advantage of 8 lifts objects to a height of 1.5 meters how long is the ramp