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3 years ago

Can someone please help!!

Physics

1 answer:

frosja888 [35]3 years ago

7 0

Answer:

Weight needed to balance the bar is $8.5N$

Explanation:

Given the weight of the bar is $8N$

The length of the bar is $5m$

The weight of the bar will be uniformly distributed over the entire span. We will consider this as a point load acting in the middle of span length, which is at a distance of $2.5m$ from both ends.

Now applying momentum equation about balanced load we get, (see attachment)

$\sum m_i=0\\2(m)+8(1)-8(0.5)-7(3)=0\\2m+8-4-21=0\\2m-17=0\\2m=17\\m=\frac{17}{2}=8.5\\So,\ m=8.5N$

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