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3 years ago

A very good insulator has an R-value of 29. The material's heat transfer coefficient is

Physics

1 answer:

Fittoniya [83]3 years ago

4 0

Answer:

b. 0.034

Explanation:

The heat transfer coefficient of a material (U-value) is equal to the reciprocal of its R-value, therefore:

$U = \frac{1}{R}$

where

R is the R-value of the material

For the insulator in this problem,

R = 29

Substituting into the equation, we find the heat transfer coefficient:

$U=\frac{1}{29}=0.034$

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FREE BRAINLIEST! if you can answer this correctly ill give you brainliest and answer some of the questions you have posted :) th

Temka [501]

Answer:3,600 Newtons

Explanation:

The net force acting on the car is

3×10^3squared

Newtons.

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2 years ago

The parallel plates in a capacitor, with a plate area of 7.90 cm2 and an air-filled separation of 2.70 mm, are charged by a 7.90

s2008m [1.1K]

Answer:

A) 26V

Explanation:

(a) the potential difference between the plates

Initial capacitance can be calculated using below expresion

C1= A ε0/ d1

Where d1= distance between = 2.70 mm= 2.70× 10^-3 m

ε0= permittivity of space= 8.85× 10^-12 Fm^-1

A= area of the plate = 7.90 cm2 = 7.90 ×10^-4 m^2

If we substitute the values we

C1= A ε0/ d1

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Initial charge can be determined using below expresion

q1= C1 × V1

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If we substitute we have

q1= 2.589 ×10^-12 × 7.90

q1= 20.45×10^-12C

20.45 pC

Final capacitance can be calculated as

C2= A ε0/ d2

d2=8.80 mm= /8.80× 10^-3

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C1=0.794 ×10^-12 F= 0.794 pF

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q2=q1 (since the battery is disconnected)

q2=q1= 20.45 pC

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3 years ago

How much force is needed to accelerate a 1000Kg car at a rate of 3m/s2?

ikadub [295]

According to Newton (2nd law), Force = (mass) x (acceleration)

Substitute what we know : Force = (1,000 kg) x (3 m/s²)

Do the arithmetic: Force = 3,000 kg-m/s² = 3,000 newtons

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3 years ago

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Three strings, attached to the sides of a rectangular frame, are tied together by a knot as shown in the figure. The magnitude o

Anna [14]

The magnitude of the tension in the string marked A is 52.5N

Generally, the equation for is mathematically given as

Let's take θ be an angle at A

So, tanθ = 3/8

Let's take α be an angle at B (Below X)

tanα = 5/4

Let's take β be an angle at C (Below x)

tanβ = 1/6

First we take the Horizontal Components

74.9cos(9.46°) = Acos(20.6°) + Bcos(51.3°)

By solving the equation, we get

A = 78.9 - 0.668B … (1)

Now, we take the vertical components

74.9sin(9.46°) + Asin(20.6°) = Bsin(51.3°)

By solving the equation, we get

40.07 = 1.015B

B = 39.5N

By substituting the value of B in equation (1)

A = 78.9 - 0.6668× 39.5

A = 52.5N

Hence, the magnitude of the tension in the string marked A is 52.5N

Learn more about Tension here brainly.com/question/2287912

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2 years ago

The inventor of the electric cell was:<br> O Coulomb<br> Franklin<br> o Gilbert<br> O Volta

Tomtit [17]

Answer:

The inventor of the electric cell was:

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Explanation:

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