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AysviL [449]
3 years ago
14

At one instant, force → F = 4.0 ˆ j N acts on a 0.25 kg object that has position vector → r = ( 2.0 ˆ i − 2.0 ˆ k ) m and veloci

ty vector → v = ( − 5.0 ˆ i + 5.0 ˆ k ) m / s . About the origin and in unit-vector notation, what are (a) the object’s angular momentum and (b) the torque acting on the object?
Physics
1 answer:
eduard3 years ago
3 0

Answer with Explanation:

We are given that

Force,F=4.0 jN

Mass of object,m=0.25 kg

Position vector,r=(2.0i-2.0k) m

Velocity vector,v=(-5.0 i+5.0 k) m/s

a.We have to find the angular momentum of object.

Angular momentum with respect to origin is given by

l=m(r\times v)

Using the formula

l=0.25((2i-2k)\times (-5i+5k))

l=0.25\times\begin{vmatrix}i&j&k\\2&0&-2\\-5&0&5\end{vmatrix}

l=0.25(-j)(10-10)=0

b.Torque acting on the object,\tau=r\times F

\tau=(2i-2k)\times 4j=(8i\times j-8k\times j)=(8k+8i)Nm

Where i\times j=k,k\times j=-i

\tau=(8i+8k) Nm

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The minimum frequency of light needed to eject electrons from a metal is called the threshold frequency, ????0 . Find the minimu
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3 years ago
1. The resistance of an electric device is 40,000 microhms. Convert that measurement to ohms.
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Answer:

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Explanation:

Hopefully this helps

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