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2 years ago

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A particle (charge = 5.0 μC) is released from rest at a point x = 10 cm on the x-axis. If a 5.0-μC charge is held fixed at the o

rigin, what is the kinetic energy of the particle after it has moved 90 cm?

1 answer:

victus00 [196]2 years ago

4 0

Answer:

Explanation:

Given

Two charges with charge $Q=5\ \mu C$

When the first charge is at $x=10\ cm$ on the x-axis and another at x=0 (origin)

there is only Potential Energy

Total Energy(E)=Kinetic Energy(K)+Potential Energy(U)

$U_i=\frac{kQ\cdot Q}{r}$

$U_i=\frac{9\times 10^9\times (5\times 10^{-6})^2}{0.1}$

$U_i=2.25\ J$

$E=2.25$

When First charge is at $x=90$

There will be both Kinetic energy and potential Energy

$U_f=\frac{kQ\cdot Q}{r}$

$U_f=\frac{9\times 10^9\times (5\times 10^{-6})^2}{0.9}$

$U_f=0.25\ J$

As total Energy is constant therefore Kinetic Energy is

$k=E-U_f$

$k=2.25-0.25=2\ J$

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Explanation:

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System diagram for given situation is shown in attached Fig. 1

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<h3>PROOF:</h3>

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from Fig 3 it can be seen that fs is force by which the cylinders roll without slipping as they oscillate

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Using (6) in (8)

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2 years ago

The magnetic field around a current-carrying wire is ________proportional to the current and _________proportional to the distan

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Explanation:

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Now if I'=3I and r'=2r then magnetic field B' is given by

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Thus If the current triples while the distance doubles, the strength of the magnetic field increases by <u><em>one and half (1.5)</em></u> times.

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2 years ago

Read 2 more answers

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Answer:

d. 37 °C

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$T_{ci}$ = Initial temperature of calorimeter = 20 °C

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2 years ago

An electron is released from rest at a distance of 9.00 cm from a proton. If the proton is held in place, how fast will the elec

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Answer:

v = 61.09m/s

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When the electron is at 3.00cm from the proton the electron has traveled a distance of 9.00cm - 3.00cm = 6.00cm = 0.06m = x

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2 years ago

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