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3 years ago

A person starts running from 2 m/s to 6 m/s in 2 seconds.

Physics

1 answer:

fiasKO [112]3 years ago

8 0

Answer:

2 m/s²

Explanation:

From the question given above, the following data were obtained:

Initial velocity (u) = 2 m/s

Final velocity (v) = 6 m/s

Time (t) = 2 s

Acceleration (a) =?

The acceleration of the person can be obtained as follow:

v = u + at

6 = 2 + (a×2)

6 = 2 + 2a

Collect like terms

6 – 2 = 2a

4 = 2a

Divide both side by 2

a = 4 / 2

a = 2 m/s²

Therefore, the acceleration of the person is 2 m/s²

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A ball is being thrown straight upward and rises to a maximum height of 12.0m above its launch point. At what height above it’s

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Answer:

9.0 m

Explanation:

Let the initial velocity be 'u'.

Given:

Final velocity is half of initial velocity.

Maximum height reached by ball (H) = 12.0 m

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Now, first, we will find initial velocity of the ball using equation of motion given as:

$v^2=u^2+2a(\Delta y)$

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So, final velocity (v) = $\frac{u}{2}=\frac{15.34}{2}=7.67\ m/s$

Now, again using the same equation and finding the new height now. Let the new height be 'h'.

So, equation of motion is given as:

$v^2=u^2+2ah\\7.67^2=15.34^2+2\times -9.8\times h\\58.83=235.2-19.6h\\\\19.6h=235.2-58.83\\\\19.6h=176.37\\\\h=\frac{176.37}{19.6}\approx9.0\ m$

Therefore, the height reached by the ball when velocity is decreased to one-half of the initial velocity is 9.0 m.

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3 years ago

A light source radiates 60.0 W of single-wavelength sinusoidal light uniformly in all directions. What is the average intensity

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Given

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Inserting values

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a mass of 1.00 kg of water at temperature T is poured from a height of 0.100 km into a vessel containing water of the same tempe

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Answer:

1.34352 kg

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