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## Homework Statement

A resting hockey puck is hit with a force of 15.3 N. The frictional force slowing the puck down is 1.0 N.

a) Find the net horizontal force acting on the puck while the stick is in contact with the puck.

b) If the puck leaves the stick with a velocity of 45 m/s, how far will the puck travel in 3.0 s?

## Homework Equations

F

_{net (h)}= F

_{applied}+ F

_{f}

a = F/m

Δd = v

_{1}Δt + 1/2 aΔt

^{2}

## The Attempt at a Solution

a) F

_{net (h)}= F

_{applied}+ F

_{f}

F

_{net (h)}= (15.3 N [forward]) + (1.0 N [backward ])

F

_{net (h)}= (15.3 N [forward]) + (-1.0 N [forward])

= 14.3 N [forward]

F

_{net (h)}= 14 N [forward]

c)m = 164 g = 0.164 kg

a = F/m

a = -1.0 N [forward] / 0.164 kg

a= -6.1 m/s

^{2}[forward]

Δd = v

_{1}Δt + 1/2 aΔt

^{2}

Δd = (45 m/s) (3.0 s) + ½ (-6.1 m/s

^{2}) (3.0 s)

^{2}

Δd = 108 m (should I add a direction here, if yes then would it be 108 m [forward]?)

The puck will travel 108 m in 3.0 s.

Is this correct?