A boy drops a 0.10 kg stone down a 150 m well and listens for the echo. The air temperature is 20°C. How long after the stone is dropped will the boy hear the echo? The speed of sound through air at 20°C is v = 343 m/s.

What is an accurate definition of a heat engine?

Three resistors: R: = 3, Rz = 62, and R. = 90 are connected in series to each other and to a 36 V battery. What is the ammeter reading after the switch is closed? A. 6A B. SA C. 4 A D. 3 A E. 2 A

A force of 1 pounds is required to hold a spring stretched 0.1 feet beyond its natural length. How much work (in foot-pounds) is done in stretching the spring from its natural length to 1.1 feet beyond its natural length

Your friend, who is age 15 and has a resting heart rate of 70, wishes to start a jogging program. What would you suggest as a proper starting target heart rate? 138 115 178 155

Which of the following is the best example of sequencing data? A.) Placing cities in groups based on presence of mountains or sea shores. B.) Placing cities in groups based on the types of vegetation that grow in each city. C.

What is electrical conductivity?

According to the law of universal gravitation, as mass increases, gravity As distance increases, gravity

You and your friends are doing physics experiments on a frozen pond that serves as a frictionless, horizontal surface. Sofia, with mass 80.0 kg, is given a push and slides eastward. Elena, with mass 55.0 kg, is sent sliding northward.

Which practice fits the definition of conservation? using more of a mineral resource than needed not using a necessary mineral resource at all mining a mineral without regard to the surface soil and vegetation above it recycling cans that contain a

The word family implies that the elements in a family have like properties. What property do the elements of the noble gas family all share?