Why does every element except hydrogen need at least one neutron and its nucleus?

Within visible light, violet has the lowest frequency. a. True b. False

Find the weight of the same object on a planet where the gravitational attraction has been reduced to 1/10 of the earth's pull.

Describe how a shovel makes moving dirt easier. Use the words "resistant force," "effort force," and "distance." Tell what kind of simple machine a shovel is.

What is the celestial sphere? A. The celestial sphere is a representation of how the entire sky looks as seen from Earth. B. The celestial sphere is a model that shows the true locations in space of the Sun and a few thousand of the nearest stars. C.

On Earth, how much force is needed to lift something with a mass of 200g?

The period of a 440 Hertz sound wave is __ seconds. 1/440 1/220 220 440

Match the term to the correct description. ~A type of circuit where part of the loop is broken. ~The flow of electrons. ~A loop that creates a pathway for electricity to follow. ~A type of circuit with only one path for the electricity to follow.

What is the mass of an object that is accelerating at 10 m/s^2 when a force of 2,386 N is exerted

According to the U. S. Green Building Council, what percentage of the world's energy use and greenhouse gas emissions can be attributed to buildings?

Magnets are often fitted to the doors of refrigerators and cupboards WHY?