A 75 kg astronaut is in space fixing a satellite when you need to consult the repair manual. So, a second
astronaut throws the manual in a straight line towards the first astronaut, at 3.0 m / s
in relation to spacecraft. Astronaut 1 is at rest in relation to spacecraft
before grabbing the 2 kg manual. Determine (in relation to spacecraft) (a) the
speed of astronaut 1 right after grabbing the book, (b) the initial kinetic energies and
end of the book-astronaut system and (c) the momentum exerted by the manual on the
astronaut. (d) Finally, determine the speed of the astronaut, before and after
grab the manual, in the reference center of mass of the manual-astronaut system.

Astone dropped into a well is heard to strike the water after 8seconds. find the depth of the well if the velocity of sound is 350m/s

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?

Astudent creates a model of a closed ecosystem by filling a glass tank half full with water, then adding 10 snails and two small aquatic plants. the next day, all the snails are dead. what is the most likely cause of their death?