Which two forms of electromagnetic energy are used to produce the
most spectacular fluorescence when placed in darkness?
1. microwaves and x rays
2. microwaves and infrared
3. ultraviolet and x rays
4. ultraviolet and infrared

Answer:

a) The specific heat capacity means the amount of heat needed by a unit mass of a material to increase its temperature in one unit.

b) Liquid P - [tex]Q = 3840\,J[/tex], Liquid Q - [tex]Q = 5500\,J[/tex], Liquid R - [tex]Q = 7800\,J[/tex], Liquid S - [tex]Q = 2856\,J[/tex]

Explanation:

a) The specific heat capacity means the amount of heat needed by a unit mass of a material to increase its temperature in one unit.

b) Let suppose that heat transfer rates between liquids and surroundings are stable. The quantity of the heat released is determined by the following expression:

[tex]Q = m\cdot c\cdot (T_{r} - T_{f})[/tex] (1)

Where:

[tex]m[/tex] - Mass of the liquid, in kilograms.

[tex]c[/tex] - Specific heat capacity, in joules per kilogram-degree Celsius.

[tex]T_{r}[/tex] - Initial temperature of the sample, in degrees Celsius.

[tex]T_{f}[/tex] - Freezing point, in degrees Celsius.

Liquid P ([tex]m = 1\,kg[/tex], [tex]c = 160\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 6\,^{\circ}C[/tex])

[tex]Q = (1\,kg)\cdot \left(160\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 6\,^{\circ}C)[/tex]

[tex]Q = 3840\,J[/tex]

Liquid Q ([tex]m = 1\,kg[/tex], [tex]c = 220\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 5\,^{\circ}C[/tex])

[tex]Q = (1\,kg)\cdot \left(220\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 5\,^{\circ}C)[/tex]

[tex]Q = 5500\,J[/tex]

Liquid R ([tex]m = 1\,kg[/tex], [tex]c = 300\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 4\,^{\circ}C[/tex])

[tex]Q = (1\,kg)\cdot \left(300\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 4\,^{\circ}C)[/tex]

[tex]Q = 7800\,J[/tex]

Liquid S ([tex]m = 1\,kg[/tex], [tex]c = 102\,\frac{J}{kg\cdot ^{\circ}C}[/tex], [tex]T_{r} = 30\,^{\circ}C[/tex], [tex]T_{f} = 2\,^{\circ}C[/tex])

[tex]Q = (1\,kg)\cdot \left(102\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C - 2\,^{\circ}C)[/tex]

[tex]Q = 2856\,J[/tex]

Answer:

Explanation:

When a light bulb connects to an electrical power supply, an electrical current flows from one metal contact to the other. As the current travels through the wires and the filament, the filament heats up to the point where it begins to emit photons, which are small packets of visible light.

Explanation:

1. if an object sjnks in one liquid and floats on another liquid it implies that the density of second liquid is greater than the density of first liquid

Answer:

0.775 g/cm³

Explanation:

The given parameters are;

The mass of the alcohol = 21 g

The density of the of the alcohol = 0.7 g/cm³

The mass of water with whichit is mixed = 10 g

The density of water = 1.0 g/cm³

Therefore, the mass of the mixture, m = 21 g + 10 g = 31 g

Volume = Mass/Density

The volume of the alcohol = 21 g/(0.7 g/cm³) = 30 cm³

The volume of the water = 10 g/(1.0 g/cm³) = 10 cm³

Therefore, the volume of the mixture, V = 30 cm³ + 10 cm³ = 40 cm³

The density of the mixture, ρ = (Mass, m)/(Volume, V) = m/V

∴ ρ = (31 g)/(40 cm³) = 0.775 g/cm³

The density of the mixture, ρ = 0.775 g/cm³.

Answer:

34 kg is the answer to the question

Answer:

104 times by 3.3

Explanation:

104 is the distance for 1 hour. So you need to multiply it by 3.3( because it's 3 hour and 30 minutes)

Answer: Se presentan en equilibrio a nivel atómico y/o molecular

Explanation: Sólo los iones presentan campo eléctrico pero no son estables en la naturaleza ya que tienden a encontrar al ion de carga opuesta con el cual equilibrar la carga. El estado de equilibrio de un cuerpo o materia se da al tener idéntica cantidad de electrones (-) que de protones (+)-

Answer:

D.STATIC FRICTION

Explanation:

Have a nice day

Answer:

Potential energy is energy that is stored in an object or system. It remains unaffected by the environment outside of the object or system. Kinetic energy is the energy of an object or a system's particles in motion.

Explanation:

Answer:

the thin steel wall because that wall is so very to fast broke

Answer:

They show the elements that make up a compound.

They show the three-dimensional shape of a molecule.

They show the types of atoms that make up a molecule.

They show the number of each type of atom in a molecule.

Explanation:

#keep learning!!

Answer:

True

Explanation:

The team with the most points at the end of the game is the winner.

Explanation:

[tex]C.) \: Conduction \: \\ \\ = > it \: is \: a \: process \: of \: transferring \: \\ \\ of \: heat \: from \: one \: object \: to \: another \\ \\ when \: they \: are \: in \: contact \: [/tex]

By the conduction process the heat reaches the pin.Option C is correct.

The term "heat transfer" refers to the movement of heat. The flow of heat across a system's boundary is due to a temperature differential between the system and its surroundings.

Conduction is the type of heat transfer occurs mainly in solid or by contact.In the given condition the rod is then heated continuously at one end and the pins fall off in the order 4, 3, 2, 1​.

By the conduction process the heat reaches the pin.

Hence option C is correct.

To learn more about the heat transfer refer to the link;

https://brainly.com/question/13433948

#SPJ2

Câu trả lời:

C. 60 m

Giải trình:

Cho rằng:

Tốc độ tại A, u = 5m / s

Tốc độ tại B, v = 15m / s

Độ dài quãng đường, AB =?

Tổng thời gian di chuyển = 6 giây

Hãy tính gia tốc, a:

a = (v - u) / t

a = (15 - 5) / 6

a = 1,667 m / s²

Từ :

v² = u² + 2aS

Trong đó, S = khoảng cách

15² = 5² + 2 (1.667 * S)

225 = 25 + 3,334S

225 - 25 = 3,334S

200 = 3,334S

S = 200 / 3,334

S = 59,98 m

S = 60 m

Answer:

d. elastic potential energy

Measurement tools improve the quality and quantity of our lives by making them easier and safer. The ability to precisely quantify physical qualities has arguably enormous survival value, providing humans with an adaptive, evolutionary advantage refined over thousands of years of natural selection.

#CarryOnLearning

Explanation:

sorry I've got a bad hand writing but i think ull understand more with the screenshot that I've just pinned for u there

Answer:

this guy has answed ur question lol

Answer:

a = 16 m/s²

General Formulas and Concepts:

Dynamics

Newton's Law of Motions

Explanation:

Step 1: Define

Identify variables

[Given] F = 22000 N

[Given] m = 1375 kg

[Solve] a

Step 2: Find Acceleration

Answer:

Acceleration = 4 m/s²

Explanation:

Given the following data;

Force = 8 N

Mass = 2 kg

To find the acceleration of the block;

Newton's Second Law of Motion states that the acceleration of a physical object is directly proportional to the net force acting on the physical object and inversely proportional to its mass.

Mathematically, it is given by the formula;

[tex] Acceleration = \frac {Net \; force}{mass} [/tex]

Substituting into the formula, we have;

[tex] Acceleration = \frac {8}{2} [/tex]

Acceleration = 4 m/s²

[tex]\\ \sf\longmapsto 35\%\:of 11[/tex]

[tex]\\ \sf\longmapsto 35\%\times 11[/tex]

[tex]\\ \sf\longmapsto \dfrac{35}{100}\times 11[/tex]

[tex]\\ \sf\longmapsto \dfrac{385}{100}[/tex]

[tex]\\ \sf\longmapsto 3.85KJ[/tex]

[tex]\\ \sf\longmapsto 3850J[/tex]

third down, chris is correct

Answer:

Explanation:

These Hooke's Law problems are tricky. Here's what we need to know that clears up the problem entirely. The final and also the max speed of the block will be reached at the point where the potential energy of the system is 0. So the equation we need, namely,

[tex]KE+PE=\frac{1}{2}kA^2[/tex] can be simplified down to

[tex]KE=\frac{1}{2}kA^2[/tex] and we solve this first for KE:

[tex]KE=\frac{1}{2}(85)(.30)^2[/tex] and, paying NO attention whatsoever to significant digits here (because if you did the answer you get is not one of the choices)

KE = 3.825 J.  Now we can use that value of kinetic energy and solve for the speed we need:

[tex]KE=\frac{1}{2}mv^2[/tex] so

[tex]3.825=\frac{1}{2}(.50)v^2[/tex] so

[tex]v=\sqrt{\frac{2(3.825)}{.50} }[/tex] so

v = 3.91 m/s

Answer:

I don't know 11 but in no. 10,

The ans is 3.66

Total distance = 10m+30m+15m = 55m

Total time = 5secs+7secs +3secs =15secs

Av speed = d/t =55/15 = 3.66 m/s

Answer:

ans: 13.53 × 10^17 Newton

Answer:

1. 25 J

2. 250 J

3. 900,000 J

4. 7,500 J

Explanation:

1. The distance the wheelbarrow is tilted, d = 0.5 m

The force used to tilt the wheelbarrow, F = 50 N

The work done, W = F × d

∴ W = 50 N × 0.5 m = 25 J

2. Work done, W = Force × Distance

The applied force, F = 50 N

The distance the sand is moved, d = 5 m

∴ W = 50 N × 5 m = 250 J

3. The work done, W = The load lifted × The height to which the load is lifted

∴ W = 90,000 N × 10 m = 900,000 J

The work done, W = 900,000 J

4. The work output of the skateboard = The work input × Efficiency

Given that the skateboard is an ideal machine, we have;

The work output of the skateboard = The work input = W

W = F × d

F = 15 N, d = 500 m

∴ W = 15 N × 500 m = 7,500 J

The work output of the skateboard = W = 7,500 J.

Answer:

The primary nutrients are nitrogen, phosphorus and potassium.

The intermediate nutrients are sulfur, magnesium, and calcium.

The remaining essential elements are the micronutrients and are required in very small quantities.

Answer:

The primary nutrients are nitrogen, phosphorus and potassium.

The intermediate nutrients are sulfur, magnesium, and calcium.

The remaining essential elements are the micronutrients and are required in very small quantities.

Explanation:

Answer:

C

Explanation:

Prevents further damage to the network cable.

Answer:

Quantity of charge = 80 Coulombs

Explanation:

Given the following data;

Current = 2 A

Time = 40 seconds

To find the amount of charge flowing through the light bulb;

Mathematically, the quantity of charge passing through a conductor is given by the formula;

Quantity of charge = current * time

Substituting into the formula, we have;

Quantity of charge = 2 * 40

Quantity of charge = 80 Coulombs