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Oliver and Jack take part in running competitions. Oliver's mass is half the mass of Jack and Oliver's speed is 8 times greater than that of Jack. by how much must Jack speed up if he wants to have the same kinetic energy as Oliver? jack's original speed is 3m/s Give your answer to 2 decimal places if needed.

User Zanseb
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Final answer:

Jack must increase his speed to approximately 16.97 m/s to have the same kinetic energy as Oliver, who runs at 24 m/s.

Step-by-step explanation:

To determine by how much Jack needs to speed up to have the same kinetic energy as Oliver, we can use the formula for kinetic energy, KE = 0.5 × m × v2, where m is mass and v is velocity. Since Oliver's mass is half that of Jack, let's denote Jack's mass as 2m and Oliver's mass as m. Given that Oliver's speed is 8 times Jack's original speed of 3 m/s, Oliver's speed is 8 × 3 m/s = 24 m/s.

Setting the kinetic energies equal to each other, we have:
0.5 × m × (24 m/s)2 = 0.5 × 2m × v2
which simplifies to:
576m = 2mv2
Dividing both sides by 2m, we get:
v2 = 288
Taking the square root of both sides, v = √288 ≈ 16.97 m/s.

Therefore, Jack must speed up to approximately 16.97 m/s to have the same kinetic energy as Oliver.

User Frank Ockenfuss
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