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3 years ago

15

The position of a particle moving along the x axis is given by x = (21 + 22t – 6 t2) m, where t is in s. What is the average vel

ocity during the time interval t = 1 s to t = 4 s?

1 answer:

romanna [79]3 years ago

7 0

Answer:

12m/s

Explanation:

x = (21 + 22t – 6 t2) m,

We can express change bin velocity as

dx/dt= -12t + 22

But Velocity is changing

interval t = 1 s

t = 4 s

at t = 1, x = 21 + 22(1) -6(1)^2

=37

at t = 4, x = 21 + 22(4) -6(4)^2

=13

Distance travelled at interval t = 1 s

t = 4 s

X2 - X1=13- 37. = - 24m

Velocity= displacement/ time

= 24/(3-1)=12 m/s

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4 years ago

Glycerin (C3H8O3) is a nonvolatile liquid. What is the vapor pressure of a solution made by adding 154 g of glycerin to 316 mL o

garri49 [273]

Answer:

$P_{sol}=50.4\ mm.Hg$

Explanation:

According to given:

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∵Density of water is $0.992\ g.cm^{-3}= 0.992\ g.mL^{-1}$

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<em>Upon the formation of solution the vapour pressure will be reduced since we have one component of solution as non-volatile.</em>

<u>moles of water in the given quantity:</u>

$n_w=\frac{m_w}{M_w}$

$n_w=\frac{313.5}{18}$

$n_w=17.42 moles$

<u>moles of glycerin in the given quantity:</u>

$n_g=\frac{m_g}{M_g}$

$n_g=\frac{154}{92}$

$n_g=1.674 moles$

<u>Now the mole fraction of water:</u>

$X_w=\frac{n_w}{n_w+n_g}$

$X_w=\frac{17.42}{17.42+1.674}$

$X_w=0.912$

<em>Since glycerin is non-volatile in nature so the vapor pressure of the resulting solution will be due to water only.</em>

$\therefore P_{sol}=X_w\times P_x$

$\therefore P_{sol}=0.912\times 55.32$

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3 years ago

What percentage of the takeoff velocity did the plane gain when it reached the midpoint of the runway? a plane accelerates from

ElenaW [278]

When is at the end of the runway the velocity of the plane is given by the equation $vf^{2}=0+2*a*s$ where s=1800 m is the runway length. Thus
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$vf =134.164 (m/s)$

At half runway the velocity of the plane is
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$
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6 0

3 years ago

True or false. The Ohm's Law equation includes calculations using volts, current, and couloms.

Iteru [2.4K]

Answer:false

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3 years ago

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GarryVolchara [31]

Answer:

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Step 2:

Force exterted by the horizontal rope is the centripetal force acting on theice skater:

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Fc =273.69 N

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3 years ago