What is its acceleration if it is assumed constant How much

What is its acceleration, if it is assumed constant How much time is required for the puck to rest? What is its speed after travelling 155 m?

Solution

v² = u² + 2 a s

2 a s = -u²

a = -u² / 2 s = -3² / 2 * 205

a = -0.0219 m/s²

--------------------------------------------------

v² = u² + 2 a y

v² = 3² + (2 * 0.0219 * 155)

v = 3.97 m/s