One block rests upon a horizontal surface. A second identical block rests upon the first one. The coefficient of static friction between the blocks is the same as the coefficient of static friction between the lower block and the horizontal surface. A horizontal force is applied to the upper block, and its magnitude is slowly increased. When the force reaches 52.1 N, the upper block just begins to slide. The force is then removed from the upper block, and the blocks are returned to their original configuration. What is the magnitude of the horizontal force that should be applied to the lower block, so that it just begins to slide out from under the upper block

[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]

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:

D.STATIC FRICTION

Explanation:

Have a nice day

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:

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:

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

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

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:

C

Explanation:

Prevents further damage to the network cable.

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:

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:

Speed = 1.6 m/s

Explanation:

Formula,

Speed = Distance ÷ Time

Answer:

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

Answer:

The dimension is L

Explanation:

Dimension analysis is a method of representing quantities majorly with respect to some fundamental quantities of mass (M), length (L), time (T).

A sphere has a definite volume which relates to its radius by:

V = [tex]\frac{4}{3}[/tex][tex]\pi[/tex][tex]r^{3}[/tex]

In this equation [tex]\pi[/tex] is a dimensionless quantity, and the unit of v is [tex]m^{3}[/tex].

But, metre is a measure of length, thus it has a dimension of L.

So that,

[tex]m^{3}[/tex] ≅ [tex]L^{3}[/tex]

Then,

[tex]L^{3}[/tex] = [tex]r^{3}[/tex]

Find the cube root of both sides to have,

r = L

Therefore, the dimension of the radius of a sphere is L.

Answer:

the energy produced in a body due to its motion is kinetic energy.

energy produced in a body due to its position is potential energy.

Explanation:

kinetic energy is the energy possessed by a body in motion

Potential energy is the energy possessed by a body by virtue of its position with respect to a reference level

Explanation:

Q7Answer=If light meets a rough surface, each ray obeys the law of reflection. However, the different parts of the rough surface point in different directions, so the light is not all reflected in one direction. Instead, the light is reflected in all directions. This is called diffuse scattering .

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:

I don't agree

Explanation:

Atoms have 3 subatomic particles protons, electrons and neutrons,

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:

1. A

2. B

Explanation:

Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.

Sound travels faster through solids than it does through either liquids or gases.

Wavelength can be defined as the distance from one peak to the next peak of a waveform. This distance is also equal to the distance from one trough of a wave to another.

Diffraction is a wavelength property that makes it possible for sound to be heard around a bend. Thus, it's a property that causes a change in the direction of a wave as it travels through or around a barrier (obstacle) in its path.

Simply stated, diffraction involves the bending of waves around small obstacles with their dimensions smaller than or approximately equal to the wavelength of the sound wave.

On the other hand, reflection can be defined as a phenomenon which typically involves a change in the direction of a wave (bounces back) as it falls on a surface.

Hence, reflection is the property of sounds which animals such as bats use to detect their paths as they navigate from one point to another. This phenomenon is generally referred to as echolocation and it typically involves the use of reflection (echo) of sound to gain information about the nature and location of surrounding objects.

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:

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:

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:

d. elastic potential energy

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:

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:

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:

34 kg is the answer to the question