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2 years ago

The half-life of iodine-131 is 8.04 days. It’s decay constant equals

Physics

1 answer:

Svetllana [295]2 years ago

7 0

Answer:

Explanation:

we know that half life of an element is

T=0.693/λ

where λ is decay constant in order to find decay constant

λ=0.693/T

λ=0.693/8.04

λ=0.086

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Answer:

trenchs and magma

Explanation:

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How would you find the average speed of a cyclist throughout an entire race

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3 years ago

You are going 30 m/s in a car of mass 1000 kg when you reach a red light and stop your car.

Radda [10]

Answer:

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2 years ago

Planets are not uniform inside. Normally, they are densest at the center and have decreasing density outward toward the surface.

SSSSS [86.1K]

Answer:

a = 9.94 m/s²

Explanation:

given,

density at center= 1.6 x 10⁴ kg/m³

density at the surface = 2100 Kg/m³

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$\rho(r) = ar^2 - br^3$

r is the radius of the spherical shell

dr is the thickness

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$dV = 4 \pi r^2 dr$

mass of shell

$dM = \rho(r)dV$

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now,

$dM = (\rho_0 - br)(4 \pi r^2)dr$

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$M = \int_0^{R} (\rho_0 - br)(4 \pi r^2)dr$

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we know,

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2 years ago

What is mean by combination reaction ?

mrs_skeptik [129]

$\underline{\purple{\large \sf Combination \: reaction :-}}$

Those reaction in which two or more substances combine to form a one new substance are called Combination reaction

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Two or more elements can combine to form a compound.
Two or more compounds can combine to from a one new compound.
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$\underline{\green{\large \sf For\: example :}}$

$\sf 2H_{2} + O_{2} \: \underrightarrow{Combination} \: 2H_{2}o$

In this, Hydrogen is an element and Oxygen is another element. Both are combined to form compound 'Hydrogen oxide'. Hydrogen oxide is commonly known as water.

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3 years ago