What is the atomic number of a sodium atom that has 11 protons and 12 nuetrons?

A boy that has a mass of 40 kilograms is walking at a speed of 2m/s. What is the boys momentum?

A certain 100W light bulb has an efficiency of 95%. How much thermal energy will this light bulb add to the inside of a room in 2.5h if the bulb is on for the whole time?

The FIRST step in cloud formation is ... A) warmed air cools and condenses. B) solar energy causes warm air to rise. C) solar energy causes water vapor to condense.

A 1.35 kg block is pulled across a flat, frictionless floor with a 3.07 N force at 32.0° above horizontal. What is the acceleration of the block?

What is most likely to happen to light that hits an opaque object? A. All of the light passes through the object. B. None of the light passes through the object. C. Most of the light disappears. D. Some of the light passes through the object.

What has become an important alternative to Piagetian approaches?

How would life on earth be different if earth's axis were not tilted with respect to its orbit? A. There would be no seasons. B. There would be no day and night. C. All places would have the same climate. D. The seasons would be much shorter.

What will a spring scale read for the weight of a 75.0-kg woman in an elevator that moves upward with constant speed of 5.8 m/s?

What's the definition of: • cellular respiration • photosynthesis

What are the steps that are important to take for your safety during an earthquake? a. stay away from walls and windows c. stay away from electrical and gas lines b. get under a desk or table d. all of the above