A speed skater moving across frictionless ice at 9.0 hits a 5.1 -wide patch of rough ice. She slows steadily, then continues on at 6.4 .

What is her acceleration on the rough ice?

1 answer

a = (V^2-Vo^2)/2d.
a = (40.96-81)/10.2 = -3.93 m/s^2.

"a" is negative because she was slowing down.