An earthquake 50km from a city produces p and s waves that travel outward at 5000 and 3000 m/s, respectively. once city residents feel the shaking of the p wave, how much time do they have before the s wave arrives?

The pressure increases by 1.0 x 104 n/m^2 for every meter of depth beneath the surface of the ocean. at what depth does the volume of a pyrex (bulk modulus 2.6 x 1010n/m^2) glass cube, 9.8 x 10^−2m on an edge at the ocean's surface, decrease by 7.5 x 10−10m^3? explain the formula beyond this point: p=1.0x10^4, b=2.6x10^10, l=9.8x10^−2, delta v=7.5x10^−10. at some point l needs to be cubed. why p is divided by delta v?

What do elements in a family tend to share. a.) similar periods b.) similar groups c.) similar atomic symbols d.) similar chemical properties and characteristics

Search coils and credit cards. one practical way to measure magnetic field strength uses a small, closely wound coil called a search coil. the coil is initially held with its plane perpendicular to a magnetic field. the coil is then either quickly rotated a quarter-turn about a diameter or quickly pulled out of the field. (a) derive the equation relating the total charge q that flows through a search coil to the magnetic-field magnitude b. the search coil has n turns, each with area a, and the flux through the coil is decreased from its initial maximum value to zero in a time ∆t. the resistance of the coil is r, and the total charge is q = i∆t, where i is the average current induced by the change in flux. (b) in a credit card reader, the magnetic strip on the back of a credit card is rapidly “swiped” past a coil within the reader. explain, using the same ideas that underlie the operation of a search coil, how the reader can decode the information stored in the pattern of magnetization on the strip. (c) is it necessary that the credit card be “swiped” through the reader at exactly the right speed? why or why not?