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

What is the height of a 3.00-kg object that has 300. J of energy

A long jumper leaves the ground with an initial velocity of 12 m/s at an angle of 28-degrees above the horizontal. Determine the time of flight, the horizontal distance, and the peak height of the long-jumper.

Which statement about the physical change of liquid water boiling into steam is true? The heat added represents an energy change. The action cannot be reversed. The steam cannot conserve mass. The weight lost represents a mass change.

An object is dropped from rest from a certain height. Air resistance is negligible. After falling a distance, d, the object's kinetic energy is proportional to which of the following? (A) 1/d (B)  d (C) d (D) d2

A changing climate has strong implications for biodiversity. Studies of fossil and pollen distribution show that species are very sensitive to climate changes.

For a vacation, you and your family fly east to west from Boston, Massachusetts, to Seattle, Washington. You notice that your flight back home to Boston is shorter than your flight to Seattle. Which phenomenon causes your flight home to be shorter?

You spy on an anchor on the bottom of a lake. What is the direction and amount of force the water exerts on it: a) zero b) up, equal to the weight of the anchor. c) up, less than the weight of the anchor d) down, equal to the weight of the anchor.

How are electromagnetic waves different from matter waves?

A dc generator is the same as a (n) a. electric motor. b. ac generator. c. armature. d. electric current.

Which of the following best describes scientific knowledge A.) Durable B.) Absolute and never changing C.) Frequently varies