Find the ratio of the velocities of two vehicles, one powered by a liquidchemical rocket and the other by a solid-chemical one, when they are used for acceleration of a 10,000-kg payload in a zero-gravity field. Both vehicles have a total initial mass of 510,000 kg. The liquid-propellant rocket has 60% greater specific impulse and 30% greater mass of empty vehicle (without propellant and payload), and the solid-propellant rocket has a structural coefficient of e

What is the function of the commutator in a dc motor? a. to spin the magnet b. to change direct current into alternating current c. to change alternating current into direct current d. to spin the wire coil

In a load, the load is paralel to the shaft. n a. angular n b. thrust n c radial n d. none of the above

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.