Which statement is true about alkali metals? A. Some of them explode when exposed to water. B. They are in group 18 of the periodic table. C. They are not conductors of heat or electricity. D. They are not very reactive.

How are the electric field lines around a positive charge affected when a second positive charge is rear it?

Which gas is the most abundant of the trace gases? nitrogen oxygen argon carbon dioxide

A rock with a mass of 2.9 kg falls 5.5 m. What potential energy does it have before the fall?

An elevator is accelerating upward at a rate of 3.6 m/s2. a block of mass 24 kg hangs by a low-mass rope from the ceiling, and another block of mass 90 kg hangs by a low-mass rope from the upper block.

Explain the difference between displacement and distance

you can produce a sound by plucking a string or by blowing in a pipe. how are these two ways different?

There are four springs stretched by the same mass. Spring A: 25 cm Spring B: 10 cm Spring C: 100 cm Spring D: 1 cm Which spring is the strongest? A B C D

Consider a rough asphalt roadway with 17 cm curbs and one 3.75 m lane in each direction and a 1.45 m shoulder on each side. The road has a longitudinal slope of 0.75% and is crowned in the center with a transverse slope of 2.25%.

An example of an opinion would be which of the following? bob s burgers is the best show on television. cake is appropriate for many occasions. earth is 238,900 miles from the moon. none of these

Which is a concern about mining for uranium? -Heated water could be released into the environment. -Dust released in the air could be radioactive. -Supplies could become low during a drought.