Answer:
s = 19.23 m
Explanation:
Since, the frictional force is given as:
f = μN = μW
f = μmg ----------- equation (1)
but, from Newton's 2nd Law:
f = ma -------------- equation (2)
comparing equation (1) and equation (2):
ma = μmg
a = μg
here,
a = acceleration of puck
μ = coefficient of static friction = 0.13
g = -9.8 m/s² (negative sign for slowing down of puck)
Therefore,
a = (0.13)(-9.8 m/s²)
a = -1.274 m/s²
Now, using 3rd equation of motion:
2as = Vf² - Vi²
where,
s = distance covered = ?
Vf = Final Velocity = 0 m/s (since, puck finally stops)
Vi = Initial Velocity = 7 m/s
Therefore,
2(- 1.274 m/s²)s = (0 m/s)² - (7 m/s)²
s = (- 49 m²/s²)/(- 2.548 m/s²)
s = 19.23 m
