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2 years ago

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Four objects are situated along the y axis as follows: a 1.93-kg object is at +2.91 m, a 2.95-kg object is at +2.43 m, a 2.41-kg

object is at the origin, and a 3.99-kg object is at -0.496 m.
Where is the center of mass of these objects?

1 answer:

Anna [14]2 years ago

3 0

Answer:

0.958 m

Explanation:

So the total mass of the system is

M = 1.93 + 2.95 + 2.41 + 3.99 = 11.28 kg

let y be the distance from the center of mass to the origin. With the reference to the origin then we have the following equation

$My = m_1y_1 + m_2y_2 +m_3y_3 + m_4y_4$

$11.28y = 1.93*2.91 + 2.95*2.43 + 2.41*0 + 3.99*(-0.496) = 10.806$

$y = \frac{10.806}{11.28} = 0.958 m$

So the center of mass is 0.958 m from the origin

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Answer:

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3 years ago

Where is the near point of an normal eye when accidentally wear a contact lens with a power of +2.0 diopters?

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Answer:

The near point of an eye with power of +2 dopters, u' = - 50 cm

Given:

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Solution:

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Power, P = $\frac{1}{f}$

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Thus

f = $\frac{1}{P}$

f = $\frac{1}{2}$ = + 0.5 m

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$\frac{1}{u'} = \frac{1}{0.5} - \frac{1}{0.25}$

$\frac{1}{u'} = \frac{1}{f} - \frac{1}{u}$

Solving the above eqn, we get:

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