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

An observer that stands still as the electron moves by him, will observe

If the force applied to an object remains constant, is more power needed for the object to move faster ? explain

Awater-filled u-tube manometer is used to measure the pressure inside a tank that contains air. the water level in the u-tube on the side that connects to the tank is 5 ft above the base of the tank. the water level in the other side of the u-tube (which is open to the atmosphere) is 2 ft above the base. determine the pressure within the tank.