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3 years ago

7

What’s contact force ?

2 answers:

kodGreya [7K]3 years ago

5 0

Explanation:

Contact force is any force that requires contact. An object that exerts a force on another object by touching it is exerting a contact force. Examples of contact force are friction and normal force.

Examples of a non-contact force are gravity and magnetism.

natima [27]3 years ago

4 0

Any force that requires contact force

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2 years ago

For a particular casting setup, the top of the sprue has a diameter of 0.030 m, and its length is 0.200 m. The volume flow rate

faust18 [17]

Answer with Explanation:

We are given that

Diameter=0.030 m

Length of sprue= $h_1$ =0.200 m

Metal volume flow rate,Q=0.03 $m^3/min$

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$h_1+\frac{v^2_1}{2g}=h_2+\frac{v^2_2}{2g}$

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$0.2+\frac{(0.708)^2}{2\cdot 9.8}=0+\frac[v^2_2}{2\cdot 9.8}$

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$v_2=\sqrt{4.421264}=2.1 m/s$

$Q=A_2v_2$

$5\times 10^{-4}=A_2\times 2.1$

$A_2=\frac{5\times 10^{-4}}{2.1}=2.381\times 10^{-4} m^2$

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$\eta=0.004 N.s/m^2$

$\rho=2700 kg/m^3$

Substitute the values then we get

Reynolds number= $\frac{2.1\times 0.03\times 2700}{0.004}$

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3 years ago