What is the hardest mineral in this group?

A. Calcite

B. Quartz

C. Diamond

D. Gold

According to the most widely accepted scientific explanation, how did the universe begin? A. As a collection of protons and neutrons B. As a cloud of gas and dust C. With a huge collision D. With a giant expansion

An α-particle has a charge of + 2e and a mass of 6.64 * 10-27 kg. It is accelerated from rest through a potential difference that has a value of 1.22 * 106 V and then enters a uniform magnetic field whose magnitude is 1.80 T.

You do 1200J of work with gears. If the gears do 1000J of work, what is the efficiency of the gears?

Lea has just ordered a box of "universal" litmus paper. She dips one piece into vial A, and it turns green. She dips another piece into vial B, and it turns red. Which vial, A or B, contains a greater concentration of H + ions?

Which term describes the bending of a wave as it travels into a different medium? A. Reflection B. Interference C. Diffraction D. Refraction

A pulse of red light and a pulse of blue light enter a glass block normal to its surface at the same time. after passing through the block, which pulse exits first?

An object is hanging by a string from the ceiling of an elevator. the elevator is moving upward with a constant speed. what is the magnitude of the tension in the string? an object is hanging by a string from the ceiling of an elevator.

If a running system has a total change in the heat of 437 joules, and it is running at a temperature of 321 K, what is the entropy?

A cello string 0.75 m long has a 220 hz fundamental frequency. find the wave speed along the vibrating string. answer in units of m/s.

A copper rod at 25°C is 1.5 m long. How long would it take a sound to move through the rod from one end to another? how would I do this?