Why don't you hear a sound when you move your hand back and fourth through the air

A boat traveled upstream 90 miles at an average speed of (v-3) miles per hour and then traveled the same distance downstream at an average speed of (v+3) miles per hour.

A boat is moving at a rate of 15.0 meters per second. Its speed is then decreased uniformly to 3.0 meters per second. It takes 4 seconds for the speed to decrease. What is the magnitude of the deceleration of the car?

A decrease in the density of a sample of a gas inside a balloon could be caused by a) putting the balloon in the refrigerator. b) taking the balloon outside on a hot day. c) shaping the balloon into the shape of a dog.

A resistor with R = 300 Ω and an inductor are connected in series across an ac source that has voltage amplitude 500 V. The rate at which electrical energy is dissipated in the resistor is 286 W. What is the impedance Z of the circuit?

Which of the following statements is correct? Which of the following statements is correct? The more a muscle shortens, the more power it generates. The number of muscle fibers best determines how powerful a muscle will be.

A bullet is accelerated down the barrel of a gun by hot gases produced in the combustion of gun powder. What is the average force (in N) exerted on a 0.0500 kg bullet to accelerate it to a speed of 625 m/s in a time of 1.10 ms (milliseconds)

Your boss at the Cut-Rate Cuckoo Clock Company wants to save money on materials. You are asked to reduce the balance wheel, which is cylindrical, dimensions to one-third their original values.

Which of the following conditions is not necessary to observe an interference pattern between two sets of waves? A) The waves must have the same wavelength. B) The waves must have a constant phase difference.

Calculate the change in velocity of 70 kg object being pulled with 1000N force force 10 s

Which reaction obeys the law of conservation of mass?