Question

On an air track, a 400.0g glider moving to the right at 1.70m/s collides elastically with a 497.0g glider moving in the opposite direction at 3.25m/s

Find the velocity of first glider after the collision. m/s to the left

Find the velocity of second glider after the collision. m/s to the right

Answer 1

you must know that if the collision is elastic then three things remains constant before and after collision:-
1) sum of Kinetic Energy's
2) sum of momentums
3) total energy
let us use 2nd one here
momentum=MV
let us take initial condition

Answer 2

MU-mu (as opp. direction)=MV+mv
0.93525=MV+mv------------------(a)
by conservation of Kinetic energy
MU^2+mu^2=MV^2+mv^2
4.0935625=(MV)^2/M+(mv)^2/m----------------(b)
two equations two unknowns just solve them and get answer:)