As the ambulance got closer, marge noticed that the pitch of the siren got higher. this happened because

a) the sound waves were pushed closer together.

b) the human ear increases pitch over time.

c) the ambulance was further away.

d) the volume increased.

Ingrid wrote the hypothesis below. if the temperature of a liquid increases, the density of the liquid decreases because the particles move farther apart. what are the variables in her hypothesis?

An important dimensionless parameter concerned with very high-speed flow is the mach number, defined as v/c, where v is the speed of the object such as an airplane or projectile, and c is the speed of sound in the fluid surrounding the object. for a projectile traveling at 1170 mph through air at 50 ˚f and standard atmospheric pressure, what is the value of the mach number?

1) what is the power in horsepower of a 100 watt light bulb? what is the power in kilowatts of a 200 horsepower engine? 2) if a cars engine is providing 3000 n of force to keep the car moving at 5 m/s, what is the engine’s effective power? 3) how many gallons of water will be pumped from a well 30 feet deep by a 1/2 hp engine in 1 minute? (1 gallon weighs 8.34 pounds)