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3 years ago

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What is the maximum number of 12-2 with ground nonmetallic-sheathed cables permitted in an 18-cubic-inch device box if two singl

e-pole switches on one yoke are also in the box?

2 answers:

Novosadov [1.4K]3 years ago

8 0

Answer:i think it is 35

Explanation:

i just guessed sorry im only in 5th grade

Alenkinab [10]3 years ago

6 0

Answer:

42

Explanation:

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Under normal operating conditions, the electric motor exerts a torque of 2.8 kN-m.on shaft AB. Knowing that each shaft is solid,

77julia77 [94]

Answer:

Explanation:

The image attached to the question is shown in the first diagram below.

From the diagram given ; we can deduce a free body diagram which will aid us in solving the question.

IF we take a look at the second diagram attached below ; we will have a clear understanding of what the free body diagram of the system looks like :

From the diagram; we can determine the length of BC by using pyhtagoras theorem;

SO;

$L_{BC}^2 = L_{AB}^2 + L_{AC}^2$

$L_{BC}^2 = (3.5+2.5)^2+ 4^2$

$L_{BC}= \sqrt{(6)^2+ 4^2}$

$L_{BC}= \sqrt{36+ 16}$

$L_{BC}= \sqrt{52}$

$L_{BC}= 7.2111 \ m$

The cross -sectional of the cable is calculated by the formula :

$A = \dfrac{\pi}{4}d^2$

where d = 4mm

$A = \dfrac{\pi}{4}(4 \ mm * \dfrac{1 \ m}{1000 \ mm})^2$

A = 1.26 × 10⁻⁵ m²

However, looking at the maximum deflection in length $\delta$ ; we can calculate for the force $F_{BC$ by using the formula:

$\delta = \dfrac{F_{BC}L_{BC}}{AE}$

$F_{BC} = \dfrac{ AE \ \delta}{L_{BC}}$

where ;

E = modulus elasticity

$L_{BC}$ = length of the cable

Replacing 1.26 × 10⁻⁵ m² for A; 200 × 10⁹ Pa for E ; 7.2111 m for $L_{BC}$ and 0.006 m for $\delta$ ; we have:

$F_{BC} = \dfrac{1.26*10^{-5}*200*10^9*0.006}{7.2111}$

$F_{BC} = 2096.76 \ N \\ \\ F_{BC} = 2.09676 \ kN$ ---- (1)

Similarly; we can determine the force $F_{BC}$ using the allowable maximum stress; we have the following relation,

$\sigma = \dfrac{F_{BC}}{A}$

${F_{BC}}= {A}*\sigma$

where;

$\sigma =$ maximum allowable stress

Replacing 190 × 10⁶ Pa for $\sigma$ ; we have :

${F_{BC}}= 1.26*10^{-5} * 190*10^{6} \\ \\ {F_{BC}}=2394 \ N \\ \\ {F_{BC}}= 2.394 \ kN$ ------ (2)

Comparing (1) and (2)

The magnitude of the force $F_{BC} = 2.09676 \ kN$ since the elongation of the cable should not exceed 6mm

Finally applying the moment equilibrium condition about point A

$\sum M_A = 0$

$3.5 P - (6) ( \dfrac{4}{7.2111}F_{BC}) = 0$

$3.5 P - 3.328 F_{BC} = 0$

$3.5 P = 3.328 F_{BC}$

$3.5 P = 3.328 *2.09676 \ kN$

$P =\dfrac{ 3.328 *2.09676 \ kN}{3.5 }$

P = 1.9937 kN

Hence; the maximum load P that can be applied is 1.9937 kN

4 0

3 years ago

What is programming and sensory?

NNADVOKAT [17]

Answer:

Programing is using data or codes to make something happen A sensory is like when you move your arm in front of a device and like it has a light that turns on then that is sensory it like can tell your moving

7 0

3 years ago

As the temperature of a thermal radiator is increased Group of answer choices the object appears redder. the object appears blue

Elanso [62]

Answer:

As the temperature of a thermal radiator is increased

Group of answer choices

the object appears redder.
the object appears bluer.
the object emits more power for the same area.
the object emits less power for the same area.
the object expands to keep the same power per units area.

<em>When the temperature of a thermal radiator increases ;</em>

<em>the object emits more power for the same are</em>
<em>the object becomes bluer</em>

Explanation:

Thermal radiation involves the transfer of heat between molecules of two substances without direct contact with each other. When a body is heated to a given temperature it begins to emit light which is transferred to nearby objects as thermal radiation. The medium through which the heat is transferred could be liquid, solid, or in a vacuum.

<h3>How temperature affects thermal radiation.</h3>

Temperature determines the amount of heat that is been radiated from a body. An increase in temperature would increase the thermal radiation of the body. The increase in the heat radiation results to increase in the thermal energy of the body. Also when a body is heated it tends to be bluer than a cool object, this is caused by the rapid movement of the molecules.

Therefore When the temperature of a thermal radiator increases ;

the object emits more power for the same are
the object becomes bluer

4 0

4 years ago

For a metal casting with a cylindrical riser, what is the best (optimal) aspect ratio (aspect ratio is the ratio of the riser's

DochEvi [55]

Answer:

Optimal aspect ratio = 1

Explanation:

From Chvorinov's Rule,

$T = c [\frac{volume}{surface are}]^n$

Where

T = solidification time

c = mold constant

$Volume = \frac{pi D^2 h}{4}$

$Surface areaA= pi Dh[\frac{2pi D^2}{4}$

For the riser to have the longest solidification time:

We have: D = h

$V = \frac{pi D^3}{4}$

$A = pi Dh[\frac{2pi D^2}{4}] = 1.5D^2 pi$

Therefore,

$\frac{V}{A} = \frac{\frac{pi D^3}{4}}{1.5D^2 pi}$

$\frac{V}{A} = \frac{D}{6}$

To have to longest solidification time, D = h

Therefore the best aspect ratio would be,

$\frac{D}{h} = 1$

3 0

3 years ago

Which of the following is a valid reason why a scientist might reject a scientific theory

Flauer [41]

C I think hope it helps :)

6 0

3 years ago

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