A 30w light bulb uses 600J of electrical energy in a certain period of time. In that time, it produces 450 J of light energy. The rest of the energy is wasted calculate the efficiency of the light bulb

Why would a person in north america not see the solar eclipse shown here?

Your car burns gasoline as you drive up a large mountain. What energy transformation is the car performing?

Two tuning forks produce sounds of wavelengths 3.4 meters and 3.3 meters. Given that the speed of sound is 340 m/s, approximately what beat frequency is produced when both tuning forks are struck simultaneously? A) 0.1 hertz B) 1.0 hertz C) 2.

In a basketball game, a player shoots a jump shot. Which force actually causes the player to jump? A. the push of the floor on the ball B. the player pushing down on the floor C. the floor pushing up on the player D.

What is the correct definition of pressure? a) force per volume b) gravity per unit c) force per unit area d) weight of the atmosphere

Tsunami waves are almost the same as ripples caused by throwing a rock into a pond. what is the major difference between the two?

A hot air balloon pilot wants the balloon to quickly rise several feet higher so it will be above some trees in the distance. Which best explains how the pilot can make the balloon rise? 1.

The density of pine is generally about 0.5 g/cm3. What is the mass of a 800 cm3 piece of pine Download pdf

The heat energy released or absorbed by a chemical reaction is generally determined by the difference between the energy that

A woman with a mass of * kg is standing on the rim of a large disk that is rotating at an angular velocity of 0.550 rev/s about an axis through its center. the disk has a mass of * kg and a radius of * m.