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3 years ago

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Problem 28.3 Suppose that you are planning a trip in which a spacecraZ is to travel at a constant velocity for exactly six month

s, as measured by a clock on board the spacecraZ, and then return home at the same speed. Upon your return, the people on earth will have advanced exactly one hundred years into the future. According to special relaEvity, how fast must you travel? Express your answer to five significant figures as a mulEple of c – for example, 0.95585c.

1 answer:

iragen [17]3 years ago

3 0

Answer:

v = 0.999981c m/s

Explanation:

Using the time dilation equation

$T = \frac{T_{0} }{\sqrt{1 - \frac{v^{2} }{c^{2} } } }$

T = stationary time = 100 years

T₀ = 11/12 years = 0.917 years

v = speed of travel in the space = ?

c = speed of light = 3 * 10⁸ m/s

$100 = \frac{0.917 }{\sqrt{1 - \frac{v^{2} }{(3*10^{8} )^{2} } } }\\$

$(0.917/100) ^{2} = 1 - \frac{v^{2} }{ 9 * 10^{16} }$

v = 299987395.57 m/s

v = 2.99 * 10⁸ m/s

v = 0.999981c m/s

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Answer:

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Explanation:

Given that,

Speed of the car, v = 40 mph

Energy required, $E=3.2\times 10^7 J$

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Mass of flywheel, m = 400 kg

The kinetic energy of the disk is given by :

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$\omega^2=\dfrac{2E_k}{I}$

$\omega^2=\dfrac{2E_k}{\dfrac{mr^2}{2}}$

$\omega^2=\dfrac{2\times 3.2\times 10^7}{\dfrac{400\times (0.6)^2}{2}}$

$\omega=942.80\ rad/s$

or

$\omega=943\ rad/s$

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4 years ago

A 7.5 nC point charge and a - 2.9 nC point charge are 3.2 cm apart. What is the electric field strength at the midpoint between

Oduvanchick [21]

Answer:

Net electric field, $E_{net}=91406.24\ N/C$

Explanation:

Given that,

Charge 1, $q_1=7.5\ nC=7.5\times 10^{-9}\ C$

Charge 2, $q_2=-2.9\ nC=-2.9\times 10^{-9}\ C$

distance, d = 3.2 cm = 0.032 m

Electric field due to charge 1 is given by :

$E_1=\dfrac{kq_1}{r^2}$

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$E_1=65917.96\ N/C$

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$E_2=\dfrac{kq_2}{r^2}$

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The point charges have opposite charge. So, the net electric field is given by the sum of electric field due to both charges as :

$E_{net}=E_1+E_2$

$E_{net}=65917.96+25488.28$

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4 years ago

What average net force is required to accelerate a 9.5 g

Nesterboy [21]

Answer:

2361 Newtons

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