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Nastasia [14]
2 years ago
9

The average velocity of a tennis ball is measured during serving and found to be 216 km/hr.

Physics
1 answer:
icang [17]2 years ago
7 0

Answer:

The time between hitting the ball and meeting the ground is t=0.33\: s

Explanation:

We have a semi parabolic motion here. We know that the initial speed 216 km/h or 60 m/s in the x-direction.

So we can use the following equation:

v=\frac{\Delta x}{\Delta t}

60=\frac{20}{t}

t=\frac{20}{60}

t=0.33\: s

hope it helps you!

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What product is obtained from the aldol condensation of cyclohexanone?
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Answer:

First product is FCH-OH chemically known as 2-[2-furyl(hydroxyl)methyl]-Second product is  FCH i.e (2E)-2-[2-furyl-methylene]-cyclohexanone

Explanation:

Please see the attached image for complete chemical reaction of aldol condensation of cyclohexanone

Aldol Condensation is a form of electrophilic substitution reaction in which the alpha carbon in enols or enolate anions is substituted by an electrophile to form carbon-carbon bond. Cyclohexanone also known as the first ketone consists of two alpha-carbons and four potential substitutions i.e alpha-hydrogens but none of the hydrogen on the ring is substituted. Ketones such as cyclohexanone are much more acidic than their parent hydrocarbon.

First product is FCH-OH chemically known as 2-[2-furyl(hydroxyl)methyl]-cyclohexanone  that further undergoes dehydration resulting into FCH i.e (2E)-2-[2-furyl-methylene]-cyclohexanone

Based on the explanations above, the compound formed is shown in the image.  

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2 years ago
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