A sample of copper has a volume of 23.4 cm3. if the density of copper is 8.9 g/cm3, what is the coppers mass

A train travels 160 km in 2 h. What is the train's average speed in km/h?

The frequency driving an open-closed tube is steadily raised. Resonances are heard at 500 Hz and 700 Hz with none in between.

How much more light does one collect with a 10-meter diameter telescope in 1 second than with a 0.1-meter diameter telescope in 10,000 seconds (nearly 3 hours) ? A. 1/100th as much B. 1/10th as much C. Same amount D. 10 times as much E.

From which of the following do most astronomers today think that the solar system formed? A. the sun B. asteroids C. shooting stars D. a nebula

Contrast generators and electric motors.

Why do some elements have symbols that don't use letters in the element's name?

How many (whole number of) 91 kg people can safely occupy an elevator that can hold a maximum mass of exactly 1 metric ton? A metric ton is 1.000 * 103 kg. Answer in units of people.

What are the two types of surface waves? How are they different and which one would cause more damage? Explain.

What causes a regular reflection?

43.278 kg - 28.1 g use significant figures rule