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3 years ago

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An ice skater accelerates backwards for 5.0 seconds to a final speed of 12 m/s. If the acceleration backwards was at a rate of 1

.5 m/s^2 what was the skaters initial speed?

1 answer:

Lostsunrise [7]3 years ago

4 0

Answer:

Vo = 4.5 [m/s]

Explanation:

In order to solve this problem, we must use the following equation of kinematics.

$v_{f}=v_{o}+a*t$

where:

Vf = final velocity = 12 [m/s]

Vo = initial velocity [m/s]

a = acceleration = 1.5 [m/s²]

t = time = 5 [s]

Now replacing:

$12=v_{o}+1.5*5\\v_{o}=12- (7.5)\\v_{o}= 4.5[m/s]$

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