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It is a well known fact that during a to...

It is a well known fact that during a total solar eclipse the disk of the Moon almost completely covers the disk of the Sun. From this fact and from the information your can gather from examples 2.3 and 2.4 determine the approximate diameter of the Moon.

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distance of Moon from Earth `r_(ME)=3.84xx10^(8)m`
distance of Sun form Earth `r_(SE)=1.494xx10^(11)m`
diameter of sun `D=1.39xx10^(9)m`
During solar eclipse Moon almost completely covers Sun.
Angular diameter of Moon= Angular diameter of sun

`(d)/(r_(ME))=(D)/(r_(SE))`
`:.d=D(r_(ME))/(r_(SE))`
`:.d=1.39xx10^(9)xx(3.84xx10^(8))/(1.496xx10^(11))`
`:.d=3.5679xx10^(6)`
`=3567.9xx10^(3)m`
`:.d=3567.9km`
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KUMAR PRAKASHAN-UNITS AND MEASUREMENT-SECTION -B (NUMERICALS) (ADDITIONAL EXERCISE)
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  18. If unit of a physical quantity is doubled, what will be its new value.

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