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4 years ago

What is the internal energy of 7.00 mol of n2 gas at 40c?

Physics

1 answer:

emmasim [6.3K]4 years ago

4 0

To find the internal energy of gas we can use

$U = \frac{f}{2}nRT$

here given that

Number of moles (n) = 7 moles

Temperature T = 40 + 273 = 313 K

degree of freedom(f) = 5 (for diatomic gas)

now by above formula

$U = \frac{5}{2}* 7 * 8.31 * 313$

$U = 45518.03 J$

<em>So it is approximately 45500 J (option C)</em>

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Match the following list of key words with their definitions

Korvikt [17]

Question 1 :

1. VELOCITY

2. SPEED

3. NEWTON

4. MOMENTUM

5. MASS

Question 2

1. FORCE

2. FRICTION

3. GRAVITY

4. ELECTROAGNETIC FORCE

5. ACCELERATION

6 0

2 years ago

How much heat in joules is required to melt an ice cube with a mass of 18.6 g at 0 °C? The Lf for water is 333 J/g.

EastWind [94]

Answer:

The heat energy required, Q = 6193.8 J

Explanation:

Given,

The mass of ice cube, m = 18.6 g

The heat of fusion of ice, ΔHₓ = 333 J/g

The heat energy of a substance is equal to the product of the mass and heat of fusion of that substance. It is given by the equation,

<em> Q = m · ΔHₓ joules</em>

Substituting the given values in the above equation

Q = 18.6 g x 333 J/g

= 6193.8 J

Hence, the heat required to melt the ice cube is, Q = 6193.8 J

5 0

3 years ago

A battery with an emf of 24.0 V is connected to a resistive load. If the terminal voltage of the battery is 16.1 V and the curre

lions [1.4K]

Answer:

2.03 Ω

Explanation:

EMF: This can be defined as the potential difference of a cell when it is not delivering any current. The S.I unit of Emf is Volt.

The formula of emf is given as,

E = I(R+r)............................ Equation 1

Where E = Emf, I = current, R = External resistance, r = internal resistance.

Make r the subject of the equation

r = (E-IR)/I........................ Equation 2

Note: From ohm's law, V = IR.

r = (E-V)/I........................ Equation 3

Where V = Terminal voltage

Given: E = 24 V, I = 3.9 A, V = 16.1 V.

Substitute into equation 3

r = (24-16.1)/3.9

r = 7.9/3.9

r = 2.03 Ω

6 0

3 years ago

If you could shine a very powerful flashlight beam toward the Moon, estimate the diameter of the beam when it reaches the Moon.

grin007 [14]

To develop this problem it is necessary to apply the Rayleigh Criterion (Angular resolution)criterion. This conceptos describes the ability of any image-forming device such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object, thereby making it a major determinant of image resolution. By definition is defined as:

$\theta = 1.22\frac{\lambda}{d}$

Where,

$\lambda$ = Wavelength

d = Width of the slit

$\theta$ = Angular resolution

Through the arc length we can find the radius, which would be given according to the length and angle previously described.

The radius of the beam on the moon is

$r = l\theta$

Relacing $\theta$

$r = l(\frac{1.22\lambda}{d})$

$r = 1.22\frac{l\lambda}{d}$

Replacing with our values we have that,

$r = 1.22*(\frac{(384*10^3km)(\frac{1000m}{1km})(550*10^{-9}m)}{7*10^{{-2}}})$

$r = 3680.91m$

Therefore the diameter of the beam on the moon is

$d = 2r$

$d = 2 * (3690.91)$

$d = 7361.8285m$

Hence, the diameter of the beam when it reaches the moon is 7361.82m

8 0

3 years ago

An object is placed in a fluid and then released. Assume that the object either floats to the surface (settling so that the obje

Irina18 [472]

Answer:

A. Always true

Explanation:

This is because, the buoyancy force is always present whenever and object is placed in a fluid. The magnitude of this buoyancy force is always equal to the weight of the fluid displaced by the object according to Archimedes' principle. This principle is true irrespective of whether the object floats or not. When any object is inserted in a fluid, the buoyancy force is always present irrespective of whether it floats or not.

7 0

3 years ago

Read 2 more answers