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2 years ago

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A ball dropped from rest falls freely until it hits the ground with a speed pf 20 m/s. The time during with the ball is in free

fall is approximately

1 answer:

saul85 [17]2 years ago

5 0

Answer:

$\large \boxed{\text{2.0 s}}$

Explanation:

$\begin{array}{rcl}v & = & gt\\\text{20 m$\cdot$s}^{-1} & = & \text{9.807 m$\cdot$ s}^{-2} \times t\\t & = & \dfrac{20}{9.807 \text{ s}^{-1}}\\\\& = & \textbf{2.0 s}\\\end{array}\\\text{The ball is in free fall for $\large \boxed{\textbf{2.0 s}}$}$

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Answer:

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The current magnitude of current is given by the resistance and the induced Emf as:

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$N=1300$ , $\beta=0.703$ , $A=\pi*r^2=\pi*0.10^2=0.01\pi m^2$ , $R=99.4+202=301.4$ Ω

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3 years ago

Calculate the average times it took the car to travel 0. 25 and 0. 50 meters. Record the averages, to two decimal places, in Tab

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The average speed of the given car is 2.22 s and 3.13 s for 0.25 m and 0.50 m distance respectively.

<h3>How to calculate the Average speed?</h3>

The average speed can be calculated by adding the speed of each trial divided by the number of trials,

For 0.25 m the average speed will be:

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For the 0.50 m, the average speed will:

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Therefore, the average speed of the given car is 2.22 s and 3.13 s for 0.25 m and 0.50 m distance respectively.

Learn more about Average speed:

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2 years ago

An engineer has the task of producing an aluminum alloy with a density of 3.0 grams per cubic centimeter. She comes up with the

pochemuha

Answer:

The best option is for the following option m = 15 [g] and V = 5 [cm³]

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We have that the density of a body is defined as the ratio of mass to volume.

$Ro =m/V$

where:

Ro = density = 3 [g/cm³]

Now we must determine the densities with each of the given values.

<u>For m = 7 [g] and V = 2.3 [cm³]</u>

$Ro=7/2.3\\Ro=3.04 [g/cm^{3} ]$

<u>For m = 10 [g] and V = 7 [cm³]</u>

<u /> $Ro=10/7\\Ro=1.42[g/cm^{3} ]\\$ <u />

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<u /> $Ro=15/5\\Ro=3[g/cm^{3} ]\\$ <u />

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2 years ago

Which statement is true about Gram negative organisms?

aliina [53]

Answer:

B, C and D are true.

<h3>Explanation:</h3>

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2 years ago

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LUCKY_DIMON [66]

let the distance of pillar is "r" from one end of the slab

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2 years ago