From the conservation of linear momentum, we have that the total linear momentum before the book throw is equal to the total linear momentum just after it. Since the initial velocity of the system is zero (so the initial momentum is zero), we have that:

$m_mv_m+m_bv_b=0\\\\v_m=-\frac{m_b}{m_m} v_b$

Where $m_m$ is the mass of the man, $m_b$ is the mass of the book, and $v_m$ and $v_b$ are their velocities. Plugging in the given values, we can compute the speed of the man (ignoring the negative sign, because we care about the magnitude, not the direction):

$v_m=\frac{2.40kg}{78.5kg}(11.3m/s)=0.345m/s$

In words, the resulting speed of the man is 0.345m/s.

8 0

3 years ago

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Can you please solve this for me urgently want to make sure if my answers are correct?

MA_775_DIABLO [31]

Answer:

Resolving horizontally. :

$\sum d_{x} = - (17.0 \cos 20.0) - (11.0 \cos 35.0) + (30.0 \cos 50.0) + 0 \\ { \underline{d _{x} = - 5.702 \: m}} \\ \\ \sum d _{y} = (17.0 \sin 20.0) + 12.0 - (11.0 \sin 35.0) - (30.0 \sin 50.0) \\ { \underline{d _{y} = - 11.476 \: m}}$

therefore, for resultant:

$d = \sqrt{ {d _{y} }^{2} + d _{x} {}^{2} }$

substitute:

$d = \sqrt{ {( - 5.702)}^{2} + {( - 11.476)}^{2} } \\ \\ d = \sqrt{164.211} \\ \\ { \boxed{ \boxed{ \bf{d = 12.8 \: m}}}}$

6 0

3 years ago

Why is it advisable to wear long sleeves when a student works in a chemistry lab

love history [14]

So then if they do spill the chemical then it gets on their cloths and not on then it dosen"t harm them instead it ruins their shirt.

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3 years ago

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Three equal negative point charges are placed at three of the corners of a square of side d. What is the magnitude of the net el

Rina8888 [55]

this may help you
As far as the field goes, the two charges opposite each other cancel!
So E = kQ / d² = k * Q / (d/√2)² = 2*k*Q / d² ◄
and since k = 8.99e9N·m²/C²,
E = 1.789e10N·m²/C² * Q / d²

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3 years ago

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