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 electromagnetic waves different from mechanical waves?

How much heat energy is tequired to raise the temperature of 3 kg of copper from 0

A 0.08 kg bullet traveling at speed hits a 16.1 kg block of wood and stays in the wood. The block with the bullet imbedded in it moves forward with a velocity of 8.1 m/s.

What sound frequency would a human ear NOT be able to detect? A. 100,000 Hertz B. 10,000 Hertz C. 100 Hertz D. 1,000 Hertz

What is the de Broglie wavelength of a bullet of mass 0.030 kg traveling at 540 m/s? Planck's Constant is 6.63 * 10-34 J⋅s. 4.1 * 10-35 m 3.5 * 10-35 m 2.2 * 10-34 m 1.7 * 10-34 m

On a spring break vacation you decide to visit the grand canyon near flagstaff, arizona. then you head south to visit some friends in phoenix, arizona. while on the drive you notice that the temperature is increasing along the route.

An object weighing 1.840 kg has a volume of 0.0015 m3. What is the density of the object in g/cm3?

What is the purpose of cooking using sunlight?

Two planets of the same mass are observed. Which of the following distances between the two planets would result in the least gravitational attraction? A. 90 light years B. 80 light years C. 60 light years D. 50 light years

How would you make a structure stronger?