On a break from class you decide to ride up and down all of the elevators on the upper campus. you approximate your mass to be 70 kg because that is the mass of a person we used in class last week. you guess that the elevator in the aliso lab building is going up at a speed of 10 m/s. the elevator takes 4.0 s to brake at the second floor. what is your weight before the elevator started braking

Curious carl calculated the density of a cube to be 4.50 g/cm3. what is the density of the cube in g/l?

An object has a weight of 500 on earth what is the mass of this object

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?