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2 years ago

I need help with one through six please

Physics

1 answer:

dybincka [34]2 years ago

7 0

Answer:

1] 8500000 = 8.5 × 10⁶

2] .000072 = 7.2 × 10⁻⁵

3] 5.3 × 10⁴ = 53000

4] 2.8 × 10⁻³ = 0.0028

5] Velocity = $\frac{distance}{time}$

V = $\frac{50}{10}$

V = 5 m/s

6] Acceleration = $\frac{V1-V2}{time}$

A = $\frac{30-15}{3}$

A = $\frac{15}{3}$

A = 3 m/s²

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Question:

A 63.0 kg sprinter starts a race with an acceleration of 4.20m/s square. What is the net external force on him? If the sprinter from the previous problem accelerates at that rate for 20m, and then maintains that velocity for the remainder for the 100-m dash, what will be his time for the race?

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Time for the race will be t = 9.26 s

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Given data:

As the sprinter starts the race so initial velocity = v₁ = 0

Distance = s₁ = 20 m

Acceleration = a = 4.20 ms⁻²

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