Four people are needed to lift a TV set with a single fixed pulley. How many people will be needed to lift the same TV set with a 2 fixed, 2 moveable pulley system? (Ignore friction.)

How did j. j thomson's discovery affect the model of the atom? a. it proposed that atoms are mostly composed of empty space b. it proposed that electrons orbit the nucleus like the planets in the solar system. c.

In the chemical formula for an ionic compound, which item is written first? a. positive ion b. negative ion c. subscript d. charge

A graduated cylinder is filled to 8.0 ml and a piece of granite is placed in the cylinder, displacing the level to 14.6 ml. What is the volume of the granite piece in cubic centimeters?

Balance the following equation _NaOH (aq) + _HNO3 (aq) > _NaNO3 (aq) + _H2O (1)

Acetylene (c2h2) undergoes combustion in excess oxygen to generate gaseous carbon dioxide and water. given δh°f[co2 (g) ] = - 393.5 kj/mol, δh°f[h2o (g) ] = - 241.8 kj/mol, and δh°f[c2h2 (g) ] = 226.6 kj/mol, how much energy is released (kj) when 10.

Car Q and z are put though an endurance test to see if they can travel at 120 km/h for 5.0 hours. Each car has a 45-L fuel tank. Car z must stop to refuel after traveling for 4.2 hours. Car Q, however, travels for 5.4 hours before running out of gas.

What happened to the atoms in the heated metal ball so that it didn't fit through the ring?

A 3.00 L flexible container holds a sample of hydrogen gas at 153 kPa. If the pressure increases to 203 kPa and the temperature remains constant, what will the volume be?

Measurement of the functions of a nephron reveals a glomerular capillary pressure of 69 mm Hg, and a pressure in the capsular space of 15 mm Hg.

Water is unique because the density of it's solid is less than the density of it's liquid. Describe how life would be different if this weren't true