Help me plzzz. i’ll give brainliest!!! 1. In the 1950's, an experimental train that had a mass of 2.50 x 10* kg, was powered across
a level track by a jet engine that produces a thrust of 5.00 x 10' N for a distance of 5.00 x
107 m. What is the final speed of the train if there was no friction?

2. A hockey puck is accelerated, using a hockey stick, over a smooth, level ice surface. The
puck has a mass of 0.400 kg and is moved by the stick for a distance of 0.800 m. What
was the average force applied to the puck if the final speed is 25.0 m/s?

A12-kg bag of groceries is tossed onto a table at 4.0 m/s and slides to a stop in 2.2 s . modify the equation fδt=δ (mv) to find the force of friction.

Apackage of supplies is dropped from a plane, and one second later a second package is dropped. neglecting air resistance, the relative velocity of the 1st package viewed from the second will 56) a) increase. b) be constant. c) be zero. d) depend upon their weight. e) decrease

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?