A sonar emits a sound signal of frequency 40000Hz, towards the bottom of the sea. This signal is reflected on the body of a submarine after a delay of 0.3 seconds.
Given: Speed of sound in water is 1500 m/s.

Calculate the period of this wave.

Ahanging spring stretches by 35.0 cm when an object of mass 450 g is hung on it at rest. in this situation, we define its position as x = 0. the object is pulled down an additional 18.0 cm and released from rest to oscillate without friction. what is its position x at a moment 84.4 s later? express your answer in cm.

Two steel balls, each of mass m, are welded to a light rod of length l and negligible mass and are initially at rest on a smooth horizontal surface. a horizontal force of magnitude f is suddenly applied to the rod as shown. determine (a) the instantaneous acceleration a of the mass center g and (b) the corresponding rate at which the angular velocity of the assembly about g is changing with time.

Find v1, the speed of the fluid in the left end of the main pipe. express your answer in terms of h1, h2, g, and either a1 and a2 or γ, which is equal to a1a2.