$(11$ pts$)$ A $60.-kg$ person standing on a $40.-kg$ cart $($including its load$)$ travels east at speed $10.\frac{m}{s}$ on a horizontal, frictionless surface. The person pushes off the cart and flies through the air at a speed of $2\mathrm{.}0\frac{m}{s}$ toward the west. What is the speed of the cart relative to the ground after the person pushes off? Convert your answer to mph $.$

Models: $($object$,$ kinematic, dynamic$)$

Pictorial representation: Be sure to define all your variables in the pictorial. Use velocity arrows instead of streamers, and don't forget the coordinate system. Choose descriptive subscripts for your variables. Try to simplify the subscripts.

Initial:

Final:

Math: What is the speed of the cart after the person pushes off? Show all work, starting from the symbolic equations before plugging in values. Present a logical progression, showing all the steps. Be sure to include all units throughout all calculations. Use appropriately descriptive variables and subscripts. Express your answer to the proper number of sig figs.

Convert your answer to mph $.$ Show the work.

Assess: S C U M S

Have a great winter break!

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