A geological disturbance in California produces seismic waves which are detected in Phoenix, approximately 990 km from the epicenter. If the waves travel 6.3 km/s, determine the time delay between the disturbance and the detection.

The speed of surface waves in water decreases as the water becomes shallower. Suppose waves travel across the surface of a lake with a speed of 2.3 m/sm/s and a wavelength of 1.8 mm . When these waves move into a shallower part of the lake, their speed decreases to 1.9 m/sm/s , though their frequency remains the same.  Find the wavelength of the waves in the shallower water?

The bulk modulus of the Earth is 40 GPa and the shear modulus of the earth is 25 GPa. The P wave is arrived 5 min before the S wave. Calculate the distance of the earthquake. Here, density of the Earth is 5.51 g/cm. (a) 5040 km (b) 2100 km (c) 6300 km (d) 2280 km

As you zip through space in your PPS (personal propulsion suit), your pulse rate as you count it is 121 bpm (beats per minute). This high pulse rate serves as objective evidence of your excitement. However, an observer on the Moon, an expert in pulse rate telemetry, measures your pulse rate as slower. In fact, she detects only 0.561 times the rate you count and claims that you must be pretty calm in spite of everything that is going on. How fast are you moving with respect to the Moon?