Here it is, I cannot seem to start (b) so hopefully someone can help.(adsbygoogle = window.adsbygoogle || []).push({});

An open top railroad car (initially empty and of mass M.) rolls with negigible friction along a straight horizontal track and passes under the sprout of a sand conveyor. When the car is under the conveyor, sand is dispensed from the conveyer in a narrow stream at a steady rate delta-M/delta-t=C and falss vertically from an average heighthabove the florr of the railroad car. The car has an initial speed v. and sand is filling it from timet= 0 tot= T. Express your answers to the following in terms of the given quatities andg.

a) Determine the mass M of the car plus the sand that it catches as a function of timetfor 0 <t< T.

b) Determine the speedvof the car as a function of timetfor for 0 <t< T.

c) i.) Determine the initial kinetic energy of the empty car.

ii.) Determine the final kinetic energy K final of the car and its load

iii.) Is kinetic energy conserved? Explain.

d.) Determine the expressions for the normal force exerted on the car by the tracks at the following times

i.) before t=0

ii.) for for 0 <t< T.

iii.) after t=T

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# AP prob help

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