There are 2.2 pounds in a kilogram. If a boy's mass is 40 kg, what is his weight in pounds?

Physics

2 answers:

emmainna [20.7K]3 years ago

4 0

if mass 80 pounds . the answer is 36 kg

kifflom [539]3 years ago

3 0

Hey There! :)

$40*2.2$
$=88$

Hope this helps.
-Benjamin

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Answer:

θ = 13.7º

Explanation:

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ΔU, is the change in the gravitational potential energy.
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Finally, the work done for non-conservative forces, is the work done by the friction force, along the slope, as follows:

$W_{nc} = F_{f} * d * cos 180\º \\\\ = 0.2*m*g*d* cos 180\º = -0.2*m*g*d (4)$

Replacing (2), (3), and (4) in (1), simplifying common terms, and rearranging, we have:

$\frac{1}{2}* (v_{f} ^{2} - v_{0} ^{2}) = g*d* sin\theta -0.2*g*d$

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