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3 years ago

A sprinter moving at 10 m/s slows down at a rate of 1.4 m/s2. how fast is the runner moving after 4 seconds?

Physics

2 answers:

Tema [17]3 years ago

6 0

Answer:

vf= 4.4 m/s

Explanation:

Kinematics

Because the sprinter moves with uniformly accelerated movement we apply the following formula:

vf= v₀+at Formula (1)

Where:

t : time in seconds (s)

v₀: initial speed in m/s

vf: final speed in m/s

a: acceleration in m/s²

Data

t = 4 s

v₀ = 10 m/s

a = -1.4 m/s²

Problem development

We replace data in the formula (1) to calculate the speed of the sprinter in 4 seconds :

vf = 10-1.4(4)

vf= 4.4 m/s

AURORKA [14]3 years ago

3 0

V=u+at
v=10+(-1.4 (4))
=10-5.6
=4.4m/s

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Answer:

The coefficient of kinetic friction between the puck and the ice is 0.11

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