which type of friction keeps a pile of rocks from falling apart?

Answer:

A. 61 N

Explanation:

In this system, there are three moveable pulleys. In this case, the rope will have to move six times as far as the weight will rise. In other words, the input distance is 6 times the output distance  ( d in =6⋅ d out ) . Because the efficiency is 100%, the work input is equal to the work output, so we have:

work input  = work output

f( in)  ⋅  d( in) =   f( out)  ⋅  d( out)

 f( in)  ⋅ (6 ⋅  d( out))  =  f( out)  ⋅  d( out)

 f( in)  ⋅ 6 =  f( out)

  f( in)  ⋅ 6 = 360 N

  f( in)  = 60 N  

Another way to think of this is that since the rope has to move 6 times as far as the height of the weight, the mechanical advantage will be 6. Therefore, the input force needed is  360 ÷ 6 = 60 N . Of course, 60 N will balance the object, so a force slightly greater than 60 N (like 61 N) will be required to lift it.

Final answer:

The minimum rotational frequency needed for the amusement park ride to be safe is between 0.165 and 0.215 revolutions per minute. This is calculated based on the coefficient of static friction between the riders' clothing and the wall, and the radius of the cylinder.

Explanation:

In order for the riders to not slide down the wall of the amusement park ride, the centripetal force must be greater than or equal to the force of static friction between the riders' clothing and the wall. The centripetal force is given by the formula:

Fc = (mv^2) / r

where m is the mass of the rider, v is the linear speed, and r is the radius of the cylinder. The force of static friction is given by:

fs = μsN

where μs is the coefficient of static friction and N is the normal force.

At the minimum rotational frequency, the riders will experience the maximum static friction force:

fs(max) = μsN

Substituting the values and equations, we get:

(mv^2) / r = μsN

Since the normal force N is equal to the weight of the riders, we have:

(mv^2) / r = μs(mg)

Canceling out the mass on both sides and solving for v, we get:

v = √(μsgr)

The minimum rotational frequency is the linear speed v divided by the circumference of the cylinder:

f(min) = v / (2πr)

Substituting the value of v, we have:

f(min) = √(μsg / (2π))

Using the given range for the coefficient of static friction, the minimum rotational frequency is between 0.165 and 0.215 revolutions per minute.

The acceleration due to gravity of the body is 4 ms-2.

We define the weight of an object as the product of the mass of the object and acceleration due to gravity. The value of the acceleration due to gravity varies from place to place in the universe.

From the information presented in the question;

W = mg

m =  10 kilograms

W = 40 newtons

g = W/m

g = 40 newtons/10 kilograms

g = 4 ms-2

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The magnitude of net force exerted on the frog is of 1.5 N.

Given data:

The mass of frog is, m = 0.50 kg.

The magnitude of acceleration of frog is, [tex]a = 3.0 \;\rm m/s^{2}[/tex].

As per the concept of Newton's Second law, the force applied on any object is equal to the product of mass and acceleration of an object. Then the expression is given as,

[tex]F=m \times a[/tex]

Solving as,

[tex]F = 0.50 \times 3.0\\\\F=1.5 \;\rm N[/tex]

Thus, we can conclude that the magnitude of net force exerted on the frog is of 1.5 N.

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A nanometer is equivalent to 10^-9 meter. While a centimetre is equivalent to 10^-2 meter. Therefore the conversion factors are:

1 nanometer = 10^-9 meter

1 centimeter = 10^-2 meter

So,

0.227 nanometer * (10^-9 meter / 1 nanometer) * (1 centimeter / 10^-2 meter) = 2.27 x 10^-8 centimeter

Answer:

a

Answer:

Nonrenewable:Coal, Silver, soil and diamonds  

Renewable- Water  

Explanation:

i hope this helps you to answer your question

The specific heat of aluminum is actually simply a diversion. Because we can directly compute for the specific heat of copper using the formula:

ΔH = m C ΔT

where ΔH is change in enthalpy or heat lost, m is mass, C is specific heat and ΔT is change in temp

4,600 J = 150 g * C * (100 °C - 20°C)

C = 0.38 J/g°C

Answer:

0.383 J/g°C

Explanation:

The heat emitted by the copper ball while cooling down is given by:

[tex]Q=m C_s \Delta T[/tex]

where:

m = 150 g is the mass of the ball

Cs = ? is the specific heat of copper

[tex]\Delta T=100^{\circ}C-20^{\circ}C=80^{\circ}C[/tex] is the change in temperature

We know that the heat lost by the copper ball is

[tex]Q=4.6 kJ=4600 J[/tex]

So we can re-arrange the formula to find the specific heat capacity:

[tex]C_s = \frac{Q}{m \Delta T}=\frac{4600 J}{(150 g)(80^{\circ} C)}=0.383 J/g^{\circ}C[/tex]

Answer:

the train travels 210 m

Explanation:

Kinematics equations of motion

[tex]vf=vi+a*t[/tex],   equation(1)

[tex]vf^{2} =vi^{2} +2*a*d[/tex] equation(2)

Vi= initial velocity (m/s)

Vf= final velocity (m/s)

a = acceleration [tex]m/s^{2}[/tex]

d= traveling distance (m)

known information:

vi=50m/s

a=-5[tex]m/s^{2}[/tex]

t=6 s

Calculation of the final speed replacing the information known in the equation 1

[tex]vf=50-5*6[/tex]

[tex]vf=50-30=20m/s[/tex]

Calculation of the distance replacing the information known  and the final velocity in the equation 2

[tex]20^{2} =50^{2} -2*5*d\\400= 2500-10d\\10d=2500-400\\d=2100/d\\d=210m[/tex]

An electrical insulator has" Electrons tightly bound to its atoms."The correct option is A.

An electrical insulator typically has electrons tightly bound to its atoms. This prevents the electrons from moving freely and thus inhibits the flow of electric current through the material. The lack of mobile electrons is a fundamental property that distinguishes insulators from conductors or semiconductors.

B. more protons than electrons: This option is not true because an electrical insulator can have an equal number of protons and electrons or even more electrons than protons. The balance between protons and electrons does not determine whether a material is an insulator or not.

C. Electrons that freely move: This option is not true for electrical insulators. Insulators are materials that do not conduct electricity easily, and one of the main reasons is that their electrons are tightly bound to their atoms. This lack of electron mobility prevents the easy flow of electric current.

D. Negatively charged ions: This option is not true for electrical insulators in general. Negatively charged ions refer to atoms or molecules that have gained extra electrons and carry a net negative charge. While some insulators may contain negatively charged ions, it is not a defining characteristic of electrical insulators as a whole. The primary characteristic of insulators is the inability to allow the free flow of electrons.

Therefore, The correct answer is option A.

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The average acceleration of the particle between 0 seconds and 2 seconds is 4 m/s², and it is constant. From 2 seconds to 4 seconds, the particle experiences no acceleration as it moves at a constant velocity.

The question asks about the average acceleration of a particle between 0 seconds and 4 seconds. Since the acceleration is constant and equal to 4 m/s² along the x-direction, this value itself represents the average acceleration over the given time interval. There's no need to perform any additional calculations if the acceleration doesn't change with time, as is the case here.

However, it's important to note that the value of the constant acceleration (4 m/s²) applies only between 0 seconds and 2 seconds, after which the particle travels at constant velocity and the acceleration is zero.

Answer: behaviorism

Explanation:

The psychology can be define as the scientific study of the function of the mind and the behavior associated with it. The wide discipline of psychology deals with the study of the human development, health, sports, clinical , cognitive and social behavior.

The major area of study in psychology is the behaviorism. It is a systematic approach which is used to understand the behavior of the human beings. The behavior is the response to various stimuli of the environment. The behavior is associated with the reinforcement and punishment.

The gas pressure increases as the temperature decreases is an incorrect statement. Option C is correct.

The force applied perpendicular to the surface of an item per unit area across which that force is spread is known as pressure.

It is denoted by P. The pressure relative to the ambient pressure is known as gauge pressure.

When you heat a gas, the molecules get more energy and travel quicker. Cooling the molecules, on the other hand, causes them to slow down, lowering the pressure.

The gas pressure increases as the temperature decreases is an incorrect statement.

Hence,option C is correct.

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Final answer:

The statement that is not true among the provided options is C) The gas pressure increases as the temperature decreases, because according to Gay-Lussac's law, the pressure of a gas should decrease as the temperature decreases when volume is held constant.

Explanation:

The question is asking which statement is not true regarding the behavior of gases, absolute zero, and the Kelvin scale.

Statement A) Absolute zero on the Kelvin scale is -273°C is true, because by definition absolute zero corresponds to -273.15°C, which is rounded to -273°C. This is the temperature where an ideal gas would theoretically reach zero volume.

Statement B) Liquefaction of the gas occurs at approximately -155°C is irrelevant to the correctness without additional gas-specific information, since the liquefaction temperature varies for different gases.

Statement C) The gas pressure increases as the temperature decreases is false. According to Gay-Lussac's law, for a given amount of gas at constant volume, the pressure of a gas is directly proportional to its temperature. Therefore, as temperature decreases, the pressure should also decrease assuming volume is held constant, which is not what the statement suggests.

Statement D) The gas follows a linear relationship between volume and temperature is true for an ideal gas. Figures presented in the information confirm that volume and temperature are directly and positively related for a gas following ideal behavior, with the relationship being linear up until liquefaction.

The not true statement among the options is C) The gas pressure increases as the temperature decreases.

Answer:

The brainliest response is wrong. The correct answer is t= 0.45s.

Explanation:

Answer:

Time taken, t = 30 seconds

Explanation:

It is given that,

Initial speed of the rocket, u = 0

It is lifted with a constant acceleration of, [tex]a=2\times 10^1\ m/s^2=20\ m/s^2[/tex]

Height to be attained, [tex]d=9\times 10^3\ m[/tex]

Let t is the time taken by the rocket to reach an altitude of [tex]9\times 10^3\ m[/tex]. Using the second equation of kinematics to find it as :

[tex]d=ut+\dfrac{1}{2}at^2[/tex]

[tex]d=\dfrac{1}{2}at^2[/tex]

[tex]t=\sqrt{\dfrac{2d}{a}}[/tex]

[tex]t=\sqrt{\dfrac{2\times 9\times 10^3}{20}}[/tex]

t = 30 seconds

So, the time taken by the rocket to reach given height is 30 seconds. Hence, this is the required solution.

Answer: The given statement is False.

Top down processing is based on the information that is already present in the mind. It occurs when an individual works from general concepts ( that are imprinted in the brain) to specific.

This means that impressions that are already present in the brain influences the information that is gathered with the help of five senses. Thus, top down processing is not used when an individual encounters an unfamiliar stimulus.

The living beings in an ecosystem are named biotic factors. Living beings involve plants, creatures, bacteria, parasites and many more. The non-living components of an ecosystem are named abiotic factors. In an ecosystem, few abiotic factors are sunshine, temperature, climatic gases, water, and clay.

Plants are not an example of an abiotic factor.

Further Explanation:

Many factors affect the environment such as some factors determines how much the tree can grow, why birds are migrating one place to another, and where the plants and animals are found. There are mainly two types of factors that influence the environment are

Abiotic factors are referred as a non-living part of an environment that can easily influence living organisms. These factors are very crucial for living organisms. Every plant and animal requires these factors to live. Without these factors organism can become dehydrated, and week. Examples of Abiotic factors are:

Biotic factors are referred to as all the living parts of an ecosystem. For example, animals and plants are biotic factors. These living things of the ecosystem interact with each other in different ways. Thus, plants are part of biotic factors and not part of abiotic factor.

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Answer Details:

Grade: High School  

Subject: Biology

Chapter: Ecology

Keywords:

Biotic, abiotic, sun, light, water, oxygen, plant, animal, non-living, living, ecosystem, organism, tree, grow, bird, migration.

The statement is false; horseshoe magnets produce magnetic fields, not electromagnetic energy. Electromagnetic energy is transmitted by waves with electric and magnetic fields, such as light and radio waves.

The statement (true or false) electromagnetic energy is the kind created by horseshoe magnets is false. Horseshoe magnets create magnetic fields due to their permanent magnetic properties, not electromagnetic energy. However, when electric current is used to create a magnet, as in an electromagnet, we can say that the magnetic field is created by electrical energy. On the other hand, electromagnetic energy refers to the energy transmitted by electromagnetic waves, which include light, radio waves, and x-rays. These waves have both electric and magnetic field components and carry energy through space, even in the absence of a physical medium.

To understand this better, consider that fields of force, like the ones that occur in the space around magnets, can carry energy across space. This demonstrates that the electromagnetic waves, which are basically vibrations in the electric and magnetic fields, are capable of transporting energy. So, while horseshoe magnets produce magnetic fields, they are not the source of electromagnetic energy in the way that electromagnetic waves are.

The wavelength is the distance between two adjacent peaks of the wave.

Hence, option C is correct.

The distance between two identical locations (adjacent crests) in successive cycles is known as the wavelength, and it is used to describe waveform signals that are transmitted over wires or into space. Typically, in wireless systems, this length is specified in meters (m), centimeters (cm), or millimeters (mm). The wavelength is more frequently described in nanometers (nm), which are units of 10-9 m, or angstroms, which are units of 10-10 m, for infrared (IR), visible light (UV), and gamma radiation.

Frequency, which is defined as the number of wave cycles per second, and wavelength have an inverse relationship. The wavelength of a signal decreases with increasing frequency, or we can say that wavelength and refractive index are inversely proportional to each other.

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