A sailboat tacking against the wind moves as follows: 4.7 km at 37o east of north, 4.4 km at 25o west of north, and 2.2 km at 36o east of north. The entire trip takes 1 h and 40 min. What is the displacement of the sailboat at the end of the trip? What is the magnitude of the average velocity of the sailboat for this trip?

What is the magnitude of the average instantaneous speed of the sailboat for this trip?

At what angle would the boat have sailed to reach its destination directly? Assume north is 0o and east is 90o.

How many hydrogen (h) atoms are in one molecule of sulfuric acid, h2so4? (1 points) 1 2 4 7

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?

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects