Critical mass is the ___ of material required to produce a chain reaction.

A.) minimum amount

B.) atomic mass

C.) precise amount

D.) maximum amount

Kenya has a pile of salt on the counter. She uses a pinch of it for a meal. Which of the following physical properties of the salt change? A. Density B. Shape C. Solubility D. Thermal conductivity

Which term describes a possible explanation of, or answer to, a scientific question that is based on prior knowledge or research and that is testable?

a machine is used to lift crates of oranges has an efficiency of 65%. if the machine provides 1300 newtons through a distance of 50 meters, what is the work output?

The apparent reversal of motion of planets against the backdrop of fixed stars is called

A truck at rest at a stoplight accelerates uniformly with acceleration a = 3.8 meters/second2 for 8.5 seconds after the light turns green. What is the speed of the truck in meters/second after that time interval?

An example of a stable system

What causes chemical weathering? a. damage caused by animals and plants c. natural acids b. ice wedging d. physical factors

1. Strzała o masie 20 g tuż po wystrzale ma prędkość 50 m/s. Oblicz pracę wykonaną przez zawodniczkę. Ile wynosi energia potencjalna sprężystości napiętej cięciwy? 2. Na trampolinę o współczynniku sprężystości k=2 kN/m stanął zawodnik o masie 80 kg.

Two small plastic spheres between them has magnitude 0.22 N. What is the charge on each sphere is one the other? Explain whether it can be determined from the information give, whether the charges are positive or negative.

If it has enough kinetic energy, a moleculeat the surface of the Earth can escape the Earth's gravitation. The acceleration of gravity is 9.8 m/s2, and the Boltzmanns' constant is 1.38066*10-23 J/K.