Abody rotates around a self-contained axis once every 58 days. it also revolves around
an external point, 58 million kilometers away every 88 days. it has a mass of 3.3x1023
kilograms.
a. what is the centripetal force acting on this object in newtons?
b. the object changes its rotational period from once every 58 days to once every
34 days over 7 years. what is the angular acceleration during this time in rad/s2?
c. using your response from part b, how many complete rotations will the object
make over those 7 years?

Write the equation for momentum, first using symbols for the variables, then using words for the variables.

Simple machines can a. increase force only b. decrease force only c. increase or decrease force

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?