All categories

2 years ago

How many calories are equal to one BTU? (One calorie = 4.186 J, one BTU = 1 054 J.)

Physics

1 answer:

I am Lyosha [343]2 years ago

3 0

<h2>Option C is the correct answer.</h2>

Explanation:

We need to find how many calories is 1 BTU.

Given

1 BTU = 1054 J

1 calorie = 4.186 J

So we have

1 BTU = 4.186 x 251.79 J

1 BTU =251.79 calorie

1 BTU = 252 calorie.

Option C is the correct answer.

You might be interested in

Calculate the energy in the form of heat (in kJ) required to change 75.0 g of liquid water at 27.0 °C to ice at –20.0 °C. Assume

REY [17]

Explanation:

The given data is as follows.

mass, m = 75 g

$T_{1} = 0^{o}C$

$T_{2} = 27^{o}C$

Specific heat of water = 4.18

First, we will calculate the heat required for water is as follows.

q = $m C \times (T_{1} - T_{2})$

= $75 g \times 4.18 J/g^{o}C \times (0 - 27)^{o}C$

= 8464.5 J/mol

= 8.46 kJ ......... (1)

Also, it is given that $T_{3} = -20^{o}C$ = (20 + 273) K = 293 K and specific heat of ice is 2.108 kJ/kg K.

Now, we will calculate the heat of fusion as follows.

q = $mC \times (T_{3} - T_{1})$

= $0.075 kg \times 2.108 kJ/kg K \times (-293 - 0) K$

= -46.32 kJ ......... (2)

Now, adding both equations (1) and (2) as follows.

8.46 kJ - 46.32 kJ

= -37.86 kJ

Therefore, we can conclude that energy in the form of heat (in kJ) required to change 75.0 g of liquid water at $27.0^{o}C$ to ice at $-20.0^{o}C$ is -37.86 kJ.

4 0

2 years ago

You have a resistor and a capacitor of unknown values. First, you charge the capacitor and discharge it through the resistor. By

Fittoniya [83]

Answer:

The frequency is $f = 0.221 \ Hz$

Explanation:

From the question we are told that

The time taken for it to decay to half its original size is $t = 3.40 \ ms = 3.40 *10^{-3} \ s$

Let the voltage of the capacitor when it is fully charged be $V_o$

Then the voltage of the capacitor at time t is said to be $V = \frac{V_o}{2}$

Now this voltage can be mathematical represented as

$V = V_o * e ^{-\frac{t}{RC} }$

Where RC is the time constant

substituting values

$\frac{V_o}{2} = V_o * e ^{-\frac{3.40 *10^{-3}}{RC} }$

$0.5 = e^{-\frac{3.40 *10^{-3}}{RC} }$

$- \frac{0.5}{RC} = ln (0.5)$

$-\frac{0.5}{RC} = -0.6931$

$RC = 0.721$

Generally the cross-over frequency for a low pass filter is mathematically represented as

$f = \frac{1}{2 \pi * RC }$

substituting values

$f = \frac{1}{2* 3.142 * 0.72 }$

$f = 0.221 \ Hz$

7 0

2 years ago

Calculate the flux of the vector field F⃗ =−6i⃗ +5x2j⃗ −5k⃗ , through the square of side 8 in the plane y=1, centered on the y-a

Tasya [4]

Answer:

The flux is 682.6 Wb.

Explanation:

Given that,

Vector field $F=-6i+5x^2j-5k$

We need to calculate the flux

Using formula of flux

$\phi=\int_{-4}^{4}\int_{-4}^{4}(F\cdot j\ dxdz)$

Put the value into the formula

$\phi=\int_{-4}^{4}\int_{-4}^{4}(-6i+5x^2j-5k)1\ dxdz$

$\phi=\int_{-4}^{4}\int_{-4}^{4}(5x^2)dxdz$

$\phi=2(\dfrac{x^3}{3})_{-4}^{4}\times(z)_{-4}^{4}$

$\phi=682.6\ Wb$

Hence, The flux is 682.6 Wb.

7 0

2 years ago

Trace fossils are recognized as evidence of which pre-existing life? plants plants and animals neither plants nor animals animal

photoshop1234 [79]

Answer:

a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself.

Explanation:

Trace fossils are the indirect evidence of life in the past, such as the footprints, tracks, burrows, borings, and feces left behind by animals, rather than the preserved remains of the actual animal body itself.

Fossil is the naturally preserved remains of plants and animals which somehow get trapped in amber, hair, petrified wood, oil, coal, and DNA remnants.

5 0

2 years ago

Read 2 more answers

A careful photographic survey of Jupiter’s moon Io by the spacecraft Voyager 1 showed active volcanoes spewing liquid sulfur to

Y_Kistochka [10]

Answer:

529.15 m/s

Explanation:

h = Maximum height = 70000 m

g = Acceleration due to gravity = 2 m/s²

m = Mass of sulfur

As the potential and kinetic energies are conserved

$mgh=\dfrac{1}{2}mv^2\\\Rightarrow h=\dfrac{v^2}{2g}\\\Rightarrow v=\sqrt{2gh}\\\Rightarrow v=\sqrt{2\times 2\times 70000}\\\Rightarrow v=529.15\ m/s$

The speed with which the liquid sulfur left the volcano is 529.15 m/s

7 0

2 years ago