All categories

4 years ago

Which equation best expresses the first law of thermodynamics, assuming Q is heat, U is internal energy, and W is work?

Physics

2 answers:

devlian [24]4 years ago

5 0

The first law of thermodynamics is expresses by

D. ΔU=Q-W

which means change in internal energy of system = Heat added to system minus work done by the system

All are expressed in Joules.

This law is based on principle of conservation of energy.

Likurg_2 [28]4 years ago

5 0

Answer:

(d) is the correct option '' $\Delta U=Q-W$ ''

Explanation:

The first law of thermodynamics states the law of conservation of energy i. e. heat energy can neither be created nor be destroyed. The mathematical expression that show the first law of thermodynamics is as follows:

$\Delta U=Q-W$

Where

$\Delta U$ is the change in internal energy

Q is the amount if heat added to the system

W is the work done by the system

Hence, the correct option is (d)

You might be interested in

As a clump of interstellar gas contracts to become a main-sequence star, its changing position on the H-R diagram tells us _____

Stels [109]

Answer:

how its outward appearance is changing

Explanation:

H-R diagram is a fundamental tool used to classify stars. The position of stars on the H-R diagram is dependent on its luminosity and temperature.

The position of the star is represented by its outward appearance specially the color. The hottest and brightest the star, the more it lies between the red and blue color range.

The cooler stars lie on the right side of the H-R diagram while the hot stars lie on the left side of the H-R diagram.

6 0

3 years ago

Coherent light with wavelength = 600 nm falls on two very narrow closely spaced slits and the interference pattern is observed o

Mrac [35]

Answer:

The distance between the two slits is 1.2mm.

Explanation:

The physicist Thomas Young establishes, through its double slit experiment, a relationship between the interference (constructive or destructive) of a wave, the separation between the slits, the distance between the two slits to the screen and the wavelength.

$\Lambda x = L\frac{\lambda}{d}$ (1)

Where $\Lambda x$ is the distance between two adjacent maxima, L is the distance of the screen from the slits, $\lambda$ is the wavelength and d is the separation between the slits.

If light pass through two slits a diffraction pattern in a screen will be gotten, at which each bright region corresponds to a crest, a dark region to a trough, as consequence of constructive interference and destructive interference in different points of its propagation to the screen.

Therefore, d can be isolated from equation 1.

$d = L\frac{\lambda}{\Lambda x}$ (2)

Notice that it is necessary to express L and $\lambda$ in units of millimeters.

$L = 4m \cdot \frac{1000mm}{1m}$ ⇒ $4000mm$

$\lambda = 600nm \cdot \frac{1mm}{1x10^{6}nm}$ ⇒ $0.0006mm$

$d = (4000mm)\frac{0.0006mm}{2mm}$

$d = 1.2mm$

Hence, the distance between the two slits is 1.2mm.

6 0

3 years ago

Manipulate p+x=r to solve for x

Tanzania [10]

X=r-p. Maybe I don't understand, but I am assuming that you need to isolate for X? you simply subtract p from both sides.<span />

4 0

3 years ago

Read 2 more answers

Force causes __________ dimensional objects to rotate

padilas [110]

Forces may cause a three-dimensional object to rotate. These forces are called "orthogonal force vectors" which composes of a horizontal component and vertical component, which hand-in-hand, help a body to rotate in accordance with the force applied on a part of its surface.

3 0

3 years ago

1. If the front of the red car is used as a reference point, how far away is the white van?

Ierofanga [76]

Answer:

-36 m

Explanation:

In the diagram, the front of the black car is used as reference point which is point 0. The distance from the black car to the front of the red car is 15 m while the distance from the black car to the white van is - 21 m. The negative sign means the white van is behind the black car.

If the red car is used as the reference (point 0), the distance from the black car to the red car would be -15 m and the distance from the black car to the white van would be -21 m. Hence:

Distance from red car to white van = distance from the black car to the red car + distance from the black car to the white van = -15 + (-21)

Distance from red car to white van = -15 - 21 = -36 m

3 0

3 years ago