Mechanics Momentum/spring energy question

[Mathy]

Hey as i have had some help with my thermodynamics why not my mechanics too. I have a question of four parts, a b c d, i have worked out a b and d but can't do c

A 2kg sphere attached to a light arm or length 0.5m is released from a horizontal postition to hit a 10kg carriage which is backed up by the spring with stiffness of 1kn/m. the carriage is initally at rest with the spring uncompressed. assuming elastic collision calculate

a: the speed of the sphere (3.13m/s worked out)
b: the rebound speed (-2.09m/s becasue of direction, worked out)
c:the maximum tension in the light arm after impact? i don't know
d: the maximum travel of the carriage after impact, (0.1m)

we also know speed of the carriage to be 1.04m/s

sorry i can't get the diagram up, don't know how to put it in code

carriage is on right with the sroing behind it, the pendulum swinging down to the right and rebounding left.

 

[Mathy]

oesnt matter i have done it i was doing t-mg=ma but in this case its t+mg=ma, so no need to reply