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3 years ago

A box with the mass of 20 kg at 5 m is lifted to 20 m. How much work was 7 points done?

Physics

1 answer:

kirza4 [7]3 years ago

3 0

Answer:

$2,900\: \mathrm{J}$

Explanation:

Work is given by the equation $W=F\Delta x$ where $F$ is force and $\Delta x$ is displacement.

Displacement is defined as change in position. In this case, the box moves from 5m to 20m. Its displacement is $20-5=15\:\mathrm{m}$ .

The force acting on the box is the force of gravity, given as $F_g=mg$ .

Therefore, the total work done is:

$W=F\Delta x=mg\Delta x = 20\cdot 9.81\cdot 15=2,943=\fbox{$2,900\:\mathrm{J}$}$ (two significant figures).

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jenyasd209 [6]

Answer:

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Explanation:

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3 years ago

Light waves are traveling through glass. If the wavelength of some part of the light wave is 4 x 10^(-7) m and the frequency of

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3 years ago

Consider a metal single crystal oriented such that the normal to the slip plane and the slip directions are at angles of 43.1° a

Bond [772]

Answer:

resolve shear stress = 22 MPa

Explanation:

Given data

slip plane α = 43.1°

slip directions β = 47.9°

shear stress = 20.7 MPa (3,000 psi)

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to find out

what stress will be necessary

solution

we know that

resolve shear stress = aplied stress × cosα × cosβ

resolve shear stress = 45 × cos(43.1) × cos(47.9)

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we can say that here single cristal will be yield

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4 years ago

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