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3 years ago

7

Sally and Ramona were competing in a four-lap, one-mile foot race. Sally’s style was to run at a constant rate of 12 mph. Ramona

decided to run her first three laps at 11 mph, and save a ‘kick’ in order to run a 16 mph pace for the fourth and final lap. Who wins the race, and by how many minutes or seconds?

1 answer:

svetoff [14.1K]3 years ago

7 0

Sally wins the race by 0.03 min

Explanation:

To find time = distance / velocity

Sally;

1 mile / 12 mph

= ¹/12 hrs * 60

= 5 min

Ramona;

³/4 mile ÷ 11 mph + ¹/4 mile ÷ 16 mph

= ³/44 hrs + ¹/64 hrs

= 4.09 min + 0.94 min

= 5.03 min

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Answer:

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$diagonal=74.25\cm=0.7425\ m$

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Now, electric field due to charges is given as:

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$E_2=E_3=E_4=9\times 10^9\times \frac{27\times 10^{-6}}{0.3712^2}$

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$E_y=1175510.2\ N.C^{-1}$

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We know that ( if acceleration is zero)

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