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3 years ago

Every year, new records in track and field events are recorded. Let's take an historic look back at some exciting races.

Physics

2 answers:

Alexeev081 [22]3 years ago

5 0

Answer:

Average velocity = 10.08 m/s

Explanation:

Given

Length of the track d = 100 m

Duration of the run t = 9.92 s

Solution

$Velocity = \frac{Distance}{Time} \\\\Velocity = \frac{100}{9.92} \\\\Velocity = 10.08 m/s$

Gala2k [10]3 years ago

4 0

100 meters in 9.92 seconds,
=distance/time
=100m/9.92s
=10.0806 m/s

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Which of these substances will form a basic solution in water? A. Ca(OH)2 B. H3PO4 C. H2SO4 D. HCl

podryga [215]

Basic solutions are hydroxides therefore the answer is A ca(OH)2

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3 years ago

A small balloon is released at a point 150 feet away from an observer, who is on level ground. If the balloon goes straight up a

Elza [17]

Answer:

$\dfrac{dz}{dt}=0.65\ ft/s$

Explanation:

Given that

x= 150 ft

$\dfrac{dy}{dt}= 7\ ft/s$

y= 14 ft

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$z^2=x^2+y^2$

When ,x= 150 ft and y= 14 ft

$z^2=150^2+14^2$

$z=\sqrt{150^2+15^2}$

z=150.74 ft

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By differentiating with respect to time t

$2z\dfrac{dz}{dt}= 2x\dfrac{dx}{dt}+2y\dfrac{dy}{dt}$

$z\dfrac{dz}{dt}= x\dfrac{dx}{dt}+y\dfrac{dy}{dt}$

Here x is constant that is why

$\dfrac{dx}{dt}=0$

$z\dfrac{dz}{dt}= y\dfrac{dy}{dt}$

Now by putting the values in the above equation we get

$150.74\times \dfrac{dz}{dt}=14\times 7$

$\dfrac{dz}{dt}=\dfrac{14\times 7}{150.74}\ ft/s$

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Therefore the distance between balloon and observer increasing with 0.65 ft/s.

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3 years ago

Multiple-Concept Example 6 reveiws the principles that play a role in this problem. A nuclear power reactor generates 2.3 x 109

r-ruslan [8.4K]

Answer:

change in mass = 2.41*10^{8}kg

Explanation:

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$E=\Delta mc^2\\\Delta m=\frac{E}{c^2}$ (1)

That is, the energy liberated comes from the mass of the nuclear fuel. The energy generated in one year is

$E=Pt=2.3*10^{9}\frac{J}{s}*1 year*\frac{365.25 day}{1 year}*\frac{24h}{1 day}*\frac{3600s}{1h}=7.25*10^{16}J$

Hence, by replacing in the equation (1) you have (c=3*10^{8}m/s)

$\Delta m=\frac{7.25*10^{16}J}{3*10^{8}\frac{m}{s}}=2.41*10^{8}kg$

HOPE THIS HELPS!!

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3 years ago

Read 2 more answers

Eric has a mass of 70 . He is standing on a scale in an elevator that is accelerating downward at 1.7 . What is the approximate

pychu [463]

Answer:

Explanation:

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$F=W-N=ma$

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3 years ago

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Paladinen [302]

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3 years ago