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3 years ago

15

Sr-90 has a half-life of T1/2 = 2.85 a (years). How much Sr-90 will remain in a 5.00 g sample after 5.00 a? Show all of your wor

k. (2 marks)

1 answer:

Molodets [167]3 years ago

6 0

Answer:

1.48 g

Explanation:

A = A₀ (½)^(t / T)

where A is the final amount,

A₀ is the initial amount,

t is time,

and T is the half life.

A = (5.00 g) (½)^(5.00 a / 2.85 a)

A = 1.48 g

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Distance is 50 km

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<u>Explanation:</u>

Given:

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2 years ago

A particular interaction force does work wint inside a system. the potential energy of the interaction is u. which equation rela

larisa86 [58]

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3 years ago

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valentina_108 [34]

Answer:

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Solving the equation for the time, and applying to the case: $t=\frac{v_f-v_0}{a}=\frac{0\frac{m}{s}-282\frac{m}{s} }{-201\frac{m}{s^2} }=1.40s$ , where $v_f=0\frac{m}{s}$ because the sled is totally stopped, $v_0=282\frac{m}{s}$ is the velocity of the sled before braking and, $a=-201\frac{m}{s^2}$ is negative because the deceleration applied by the brakes.

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4 years ago

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