1.8kg 42J 9.8 how high is the shelf

Answers

Answer 1

Answer:

2.38m

Explanation:

Use potential energy

PE= mgh

42= 1.8*9.8*h

solve for h

to get h= 2.38 m


Related Questions

a skydiver of mass 80kg jumpes from a plane. Taking g=m/s^2 write down the weight of skydiver

Answers

Answer:

800N

Explanation:

as we know that

weight = mass × acceleration due to gravity

= 80kg × 10 m/s^2

= 800N.

A skipper on a boat notices wave crests passing his anchor chain every 5.6 s . He estimates the distance between wave crests to be 16 m . He also correctly estimates the speed of the waves. Find this speed.

Answers

Answer:

v = 2.85 m/s

Explanation:

Given that,

A skipper on a boat notices wave crests passing his anchor chain every 5.6 s.

The distance between wave crests to be 16 m.

We need to find the speed of the waves. The speed of a wave can be calculated by the formula as follows :

[tex]v=f\lambda\\\\v=\dfrac{\lambda}{T}\\\\v=\dfrac{16}{5.6}\\\\v=2.85\ m/s[/tex]

So, the speed of the wave is 2.85 m/s.

Rajah 9 menunjukkan laluan bagi kuching Fun Run. Berapakah sesaran bagi pelari tersebut? Mula 2 km 6 km Tamat 10 km Rajah Diagram 9 O A.5 km O B.6 km O c. 10 km D. 18 km​

Answers

Answer:

jsjfj heddifii ididofi idididi hdhdii iridium didi buff joid duruvdudi 7u

Ploughing field with harrow pulled by a tractor is a modern technology​

Answers

Ploughing field with harrow pulled by a tractor being a modern technology​ is true.

What is Technology?

This involves the use of scientific knowledge to tackle different life problems and has different sectors.

Ploughing field with harrow pulled by a tractor involves machines and not manual labour which makes it a modern technology.

Read more about Technology here https://brainly.com/question/7788080

#SPJ1

Difference between gravitational force and frictional​

Answers

Explanation:

gravitational force or gravity is the force of attraction between objects that have mass.

frictional force is the forec that opposes motion (movement) when two surface are in contact. (acts in the opposite direction of motion)

so to sum it up,

- gravtional force is the force of attraction between objects that have mass.

- objects on the earth have weight because of gravitational force between them and the earth.

frictional force

- oppose motion

- slow down and stop moving objects and;

- produce heat

hope it helps :)

Answer: the difference is that they are 2 completely separate things

A jet plane is launched from a catapult on an aircraft carrier. In 2.0 s it reaches a speed of 42 m/s at the end of the catapult. Assuming the acceleration is constant, how far did it travel during those 2.0 s?

Answers

First find Acceleration

Initial velocity=u=0m/sFinal velocity=v=42m/sTime=t=2sDistance=sAcceleration=a

[tex]\boxed{\sf Acceleration=\dfrac{v-u}{t}}[/tex]

[tex]\\ \sf\longmapsto Acceleration=\dfrac{42-0}{2}[/tex]

[tex]\\ \sf\longmapsto Acceleration=\dfrac{42}{2}[/tex]

[tex]\\ \sf\longmapsto Acceleration=21m/s^2[/tex]

Using second equation of kinematics

[tex]\boxed{\sf s=ut+\dfrac{1}{2}at^2}[/tex]

[tex]\\ \sf\longmapsto s=0(2)+\dfrac{1}{2}(21)(2)^2[/tex]

[tex]\\ \sf\longmapsto s=21(2)[/tex]

[tex]\\ \sf\longmapsto s=42m[/tex]

. A radio station transmitting at a frequency of 200KH, emits waves of wavelength 1.5 km.the velocity of the radio waves is​

Answers

Answer:

Explanation: as,

v=f∧

v=200×10³×1.5×10³

v=2.7×10^7ms⁻¹

The velocity of the radio waves is 3 × 10⁸ ms⁻¹.

A radio station frequency = 200 KH

wavelength = 1.5 km

How the velocity of the radio waves are calculated?

         Radio waves in the electromagnetic spectrum has the longest wavelength and it will always be below 300GHz. The radio waves can be generated with acceleration through some charged particles. Only through the transmitter via antenna the radio waves can gets transmitted. Radio waves can be used in all the electronic devices as mobile phones, radio communication, radars and navigations.

                               V = f λ

            Velocity,  v = ( 200 × 10³ ) × ( 1.5 × 10³ )

                               = ( 300 × 10⁶ )

                             v = 3 × 10⁸ ms⁻¹.

Hence, the velocity of the radio waves is 3 × 10⁸ ms⁻¹.

Learn more about the radio waves,

https://brainly.com/question/21995826

#SPJ2

the scientist who gives the definition of work

Answers

Answer:

Work, in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. ... To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd.

Please help me with these I might need more than only 1 person to answer ​

Answers

Explanation:

a) copper

b) olive oil

Hope it helps✌✌

The density of a material in CGS system of units is 4g cm-³. In a system of units in which unit of length is 10 cm and unit of mass is 100g, the value of density of material will be...?

1) 0.04


2) 40


3) 0.4


4) 400​

Answers

[tex]\sf\underline{Solution:}[/tex]

Here , the density of the material is 4g cm³ but it is not given in CGS system.

$\sf{As\:we\:know\:that:}$

$\sf\bold{Density=}$ $\sf\dfrac{Mass}{Volume}$

$\space$

[tex]\sf{Now,according \: to \:the\:question:}[/tex]

$\sf\small{Density\:of\:the\:material=4}$ $\sf\dfrac{g}{cm^2}$

$\space$

$\sf{It\:is\:given\:that:}$

In the system of units the mass is 100gram.

$\space$

Hence,

$\sf{The\:mass\:unit\:for\:4g=}$ $\sf\dfrac{4}{100}$ $\sf{units}$

$\space$

In the system of units,the length is 10cm.

Henceforth,

$\sf\small{The\:length \:for\:1cm\:units=}$ $\sf\dfrac{1}{10}$ $\sf{units}$

$\space$

☆ Substitute the required values in the given formula-

$\sf\purple{Density=}$ $\sf\dfrac\purple{Mass}\purple{volume}$

$\space$

$\sf\underline\bold{Density\:of\:the\:material:}$

= $\sf\dfrac{4/100}{1/10^3}$ $\sf\bold{units}$

$\space$

= $\sf\dfrac{4/100}{1/1000}$ $\sf\bold{units}$

$\space$

= $\sf\dfrac{4000}{100}$ $\sf\bold{units}$

$\space$

$\sf\underline\bold\blue{=40\:units}$

$\sf\small{Therefore,option\:2nd\:is\:correct!}$

_______________________________

como previene un diafragma el embarazo​

Answers

Answer:

Un diafragma es una pieza de silicona o de goma reutilizable que cubre el cuello del útero. El diafragma se coloca dentro de la vagina con espermicida antes de tener relaciones sexuales para prevenir un embarazo. El diafragma es un dispositivo anticonceptivo que impide que los espermatozoides ingresen en el útero.

Clois what is the weight of a body in the earth, if its weig is 5Nin moon?

Answers

Explanation:

because the moon has less mass than earth, the force due to gravity at the lunar surface is only about 1/6 that on earthso,the weight of a body on earth is 6×5N =30N

1. Una carga Q1 = + 12 μC se coloca a una distancia r = 0.024 m desde una carga Q2 = + 16 μC. a) Determina la magnitud de la fuerza electrostática que actúa sobre las dos cargas, Q1 y Q2. b) ¿Es la fuerza la atracción o repulsión? 2. Determina la intensidad del campo eléctrico a una distancia radial de r = 48 mm desde una carga de Q = 24 μC. 3. Una carga Q1 = 24 mC se coloca a una distancia r = 0.032 m desde una carga Q2 = - 12 μC. a. Determina la cantidad de energía potencial eléctrica que tiene la carga Q1. b. Determina el potencial eléctrico en la posición de Q2.

Answers

Answer:

1. a. 3,000 N

b. Repulsión

2. 46.875 × 10⁶ N/C

3. a. 81,000 J

b. 6.75 × 10⁹ V

Explanation:

1. Los parámetros dados son;

Q₁ = +12 μC, Q₂ = +16 μC

La distancia entre las cargas, r = 0.024

La magnitud de la fuerza electrostática, F, entre cargas se da como sigue;

[tex]F = k \times \dfrac{Q_1 \cdot Q_2}{r^2}[/tex]

Donde, k = constante de Coulomb = 9.0 × 10⁹ N · m² / C²

Por lo tanto, obtenemos;

F = 9.0 × 10⁹ × 12 × 10⁻⁶ × 16 × 10⁻⁶ / 0.024² = 3.000

La magnitud de la fuerza electrostática, entre las cargas, F = 3000 N

(b) Dado que tanto Q₁ como Q₂ son cargas positivas, y las cargas iguales se repelen entre sí, la fuerza es la repulsión.

2) La intensidad de un campo eléctrico, E, se da como sigue;

[tex]E = \dfrac{k \cdot Q}{r^2}[/tex]

La magnitud de la carga, Q = 24 μC

La distancia donde se mide el campo, r = 48 mm = 0.048 m

Por lo tanto, E = 9.0 × 10⁹ × 12 × 10⁻⁶ / 0.048² = 46,875,000 N / C

La intensidad de un campo eléctrico, E = 46,875,000 N / C = 46.875 × 10⁶ N / C

3. La magnitud de las cargas son;

Q₁ = 24 mC

Q₂ = -12 μC

La distancia entre las cargas, r = 0.032 m

un. El potencial eléctrico de una carga, [tex]U_E[/tex] , se da de la siguiente manera;

[tex]U_E = k \times \dfrac{Q_1 \cdot Q_2}{r}[/tex]

Por lo tanto;

[tex]U_E[/tex] = 9.0×10⁹ × 24 × 10⁻³ × (-12) × 10⁻⁶ /0.032 = -81,000

La energía potencial eléctrica entre la carga, Q₁ y Q₂= -81,000 J

b. El potencial eléctrico de Q₁ en Q₂, V₁ = [tex]k \times \dfrac{Q_1 }{r}[/tex]

Por lo tanto, V₁ = 9.0×10⁹ × 24 × 10⁻³/0.032 = 6.75 × 10⁹

El potencial eléctrico de Q₁ en Q₂, V₁ = 6.75 × 10⁹ V

define Archemedics principle?​

Answers

THIS IS YOUR ANSWER :

Archimedes’ principle, physical law of buoyancy, discovered by the ancient Greek mathematician and inventor Archimedes, stating that any body completely or partially submerged in a fluid (gas or liquid) at rest is acted upon by an upward, or buoyant, force, the magnitude of which is equal to the weight of the fluid displaced by the body.

☺✍️HOPE IT HELPS YOU ✍️☺

Question 7 of 25
Which two chemical equations are balanced?
O A. 2PBrg + 3Cl2 - 2PC13 + 3Br2
O B. 2Na+ MgCl2
2NaCl + Mg
-
C. 2LIOH + 2H2S - Li2S + 2H20
D. 2AgNO3 + NaCl - NaNO3 + 2AGCI

Answers

Answer:

2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂

2Na + MgCl₂ → 2NaCl + Mg

Explanation:

A balanced chemical equation is a chemical equation that have an equal number of elements of each type on both sides of the equation

Among the given chemical reactions, we have;

2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂

In the above reaction;

The number of phosphorus, P, on either side of the equation = 2

The number of bromine atoms, Br, on either side of the equation = 6

The number of chlorine atoms, Cl, on either side of the equation = 6

Therefore, the number of elements in the reactant side and products side of the reaction are equal and the reaction is balanced

The second balanced chemical reaction is 2Na + MgCl₂ → 2NaCl + Mg

In the above reaction, there are two sodium atoms, Na,  one magnesium atom and two chlorine atoms on both sides of the reaction, therefore, the reaction is balanced

make a list of principle of lever.

Answers

Answer:

The force applied to make the object move

Answer:

input work = output work

E * ED = L* LD

Explanation:

The principle of lever is that input work is always equal to output work .

D 2. Which of the following is an example of a specific goal?
O I want to lose weight.
I want to get stronger.
O I want to be able to walk one mile in 15 minutes.
I want to improve my speed.

Answers

I want to improve my speed

Answer:

D

Explanation:

factor that affect gravitation

Answers

1) Two major factors, mass and distance, affect the strength of gravitational force on an object.

2) Most common factors that affect gravity are mass of the body, distance from centers, shape of bodies,etc. Gravity is a binding force, always acting to bind any material closure and closure inwards. If we think this way, then gravity is maximum at its centre and decreases slowly away from its centre.

hope it helps you

mark my answer as brainlist and follow

have a nice day

Given: F = k· m. g
Solve for "k"

Answers

Answer:

[tex]F = kmg \\ k = \frac{F}{mg} [/tex]

Explanation:

F = k . m . g

=> F = k . mg

[tex] = > k = \frac{F}{mg} (ans)[/tex]

A large atomic bomb produces around 8.00x1015J of energy. How much matter does that bomb turn into energy?

A)2.67x10^79kg

B)2.67x10^7kg

C)7.20x10^32kg

D)0.0889kg

Answers

Answer:

D)0.0889kg

Explanation:

If a large atomic bomb produces around 8.00x10¹⁵J of energy, then from Einstein's energy law i.e E=mc² we can calculate that the amount of matter is  0.0889kg. The correct option is D.

What is Einstein's energy law?

The Einstein Energy Law, often referred to as Einstein's famous equation relates the energy of a particle (E) to its mass (m) and the speed of light (c). The equation is as follows:

E = mc²

This equation shows that energy (E) and mass (m) are equivalent and interchangeable and that a small amount of mass can be converted into a large amount of energy. This is the basis for understanding nuclear reactions and the energy released in processes like nuclear fusion and fission.

Here in the question,

To calculate the mass that is converted into energy in an 8.00x10¹⁵J nuclear reaction, we can rearrange the equation to solve for m:

m = E / c²

where c = 3 x 10⁸ m/s is the speed of light in a vacuum.

Substituting the values, we get:

m = 8.00x10¹⁵ J / (3 x 10⁸ m/s)²

m = 0.0889kg

Therefore, a large atomic bomb that produces around 8.00x10¹⁵ J of energy converts approximately 0.0889kg of matter into energy. This is a very small amount of matter, but because is such a large number, a huge amount of energy can be released from a small amount of matter in a nuclear reaction.

To learn more about Einstein's energy law click:

https://brainly.com/question/2292817

#SPJ2

Assuming Faraday constant to be 96500c/mol and relative atomic mass of copper 63,calculate the mass of copper liberated by 2A current in 5min.ans 0.196gm ​

Answers

Answer: The mass of copper liberated is 0.196 g.

Explanation:

The oxidation half-reaction of copper follows:

[tex]Cu\rightarrow Cu^{2+}+2e^-[/tex]

Calculating the theoretical mass deposited by using Faraday's law, which is:

[tex]m=\frac{M\times I\times t(s)}{n\times F}[/tex] ......(1)

where,

m = actual mass deposited = ? g

M = molar mass of metal = 63 g/mol

I = average current = 2 A

t = time period in seconds = 5 min = 300 s (Conversion factor: 1 min = 60 sec)

n = number of electrons exchanged = 2

F = Faraday's constant = 96500 C/mol

Putting values in equation 1, we get:

[tex]m=\frac{63 g/mol\times 2A\times 300s}{2\times 96500 C/mol}\\\\m=0.196g[/tex]

Hence, the mass of copper liberated is 0.196 g.

Tick (3) the correct statement about electrostatic charges.
(a) Earthing causes positive charges to flow from the object to the ground.
(b) Similar types of electric charges attract one another.
(c) An electroscope is used to determine the presence of electrostatic charges.

Answers

Answer:

similar type of electric charges attract one another

I think this is a coorect staement

Answer:

C ) An electroscope is used to determine the presence of electrostatic charges

what is velocity ratio ?​

Answers

Answer:

the ratio of a distance through which any part of a machine moves to that which the driving part moves during the same time.pls pls mark me branilest

Examine the motion map. One animal is an antelope that is already running. The other is a cheetah that starts running after the antelope passes it. Does A or B represent the motion of the cheetah?

Answers

Answer:

A although am not seeing the cheetah

86,400 seconds into day​

Answers

Answer:

60×60×24=86,400

Explanation:

i.e. 86,400 secs is 1 day

1 hour = 60 minutes

1 minute = 60 seconds

1 day = 24 hours

60 min. × 60 sec. × 24 hr.

60 × 60 × 24 = 86,400 seconds

∴ 86,400 seconds = 1 day

In a lunar experiment, a 950-g aluminum (920 J/(°Ckg)) sphere is dropped from the space probe while is 75 m above the Lunar ground. If the sphere’s temperature increased by 0.11°C when it hits the ground, what percentage of the initial mechanical energy was absorbed as thermal energy by the aluminum sphere?

Answers

Answer:

13.759 % of the initial mechanical energy is lost as thermal energy.

Explanation:

By the First Law of Thermodynamics we know that increase in internal energy of the object ([tex]U[/tex]), in joules, is equal to the lost amount of the change in gravitational potential energy ([tex]U_{g}[/tex]), in joules:

[tex]\frac{x}{100} \cdot \Delta U_{g} = \Delta U[/tex] (1)

Where [tex]x[/tex] is the percentage of the energy loss, no unit.

By definition of the gravitational potential energy and internal energy, we expand this equation:

[tex]\frac{x\cdot m \cdot g \cdot h}{100} = m\cdot c\cdot \Delta T[/tex] (1b)

Where:

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

[tex]g[/tex] - Gravitational acceleration, in meters per square second.

[tex]h[/tex] - Initial height of the object above the lunar ground, in meters.

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

[tex]\Delta T[/tex] - Temperature increase due to collision, in degree Celsius.

If we know that [tex]m = 0.95\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]h = 75\,m[/tex], [tex]c = 920\,\frac{J}{kg\cdot ^{\circ}C}[/tex] and [tex]\Delta T = 0.11\,^{\circ}C[/tex], then the percentage of energy loss due to collision is:

[tex]x = \frac{100\cdot c\cdot \Delta T}{g\cdot h}[/tex]

[tex]x = \frac{100\cdot \left(920\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (0.11\,^{\circ}C)}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (75\,m)}[/tex]

[tex]x = 13.759\,\%[/tex]

13.759 % of the initial mechanical energy is lost as thermal energy.

What would be the acceleration in a body moving with uniform velocity and why?​

Answers

Explanation:

The derivative of a constant term is always 0. So the acceleration of the body would be zero. Hence, the acceleration of a body moving with uniform velocity will always be zero.

hope it helps you

how can we maintain peace in the nature and surrounding​

Answers

Answer:

6 Ways To Promote Peace

Treat all people with kindness, regardless of race, gender orientation, sexual orientation, religion, etc.

Attend a peace rally.

Write to your government (local and federal)

Create a peaceful affirmation/mantra.

Don't engage in violence of any kind.

Don't purchase weapons.

An ant moves towards the plane mirror with speed of 2 m/s & the mirror is moved towards the ant with the same speed. What is the relative velocity between the ant and its image?​

Answers

Speed of ant-V_a=2m/sSpeed of mirror =v_b=2m/s

We know

[tex]\boxed{\sf Relative\:velocity(V_{AB})=V_A-V_B}[/tex]

[tex]\\ \sf\longmapsto V_{AB}=2-2[/tex]

[tex]\\ \sf\longmapsto V_{AB}=0m/s[/tex]

The vector difference between the velocities of two bodies : the velocity of a body with respect to another regarded as being at rest  compare relative motion

[tex]Relative velocity $\left(\mathrm{V}_{\mathrm{AB}}\right)=\mathrm{V}_{\mathrm{A}}-\mathrm{V}_{\mathrm{B}}$$$\begin{aligned}&\longmapsto \mathrm{V}_{\mathrm{AB}}=2-2 \\&\longmapsto \mathrm{V}_{\mathrm{AB}}=0 \mathrm{~m} / \mathrm{s}\end{aligned}$$[/tex]

What is relative velocity and its unit?

The relative velocity of an object with respect to another is the velocity with which one object moves with respect to another object. The unit of velocity can be referred to as the ratio of unit of distance and that of time. The SI unit of Relative velocity is meter per second.

What is absolute velocity?

The concept of absolute velocity is mainly used in turbomachinery design and defines the velocity of a fluid particle in relation to the surrounding, stationary environment. Together with the relative velocity (w) and the circumferential speed (u), it forms the velocity triangle.

To learn more about relative velocity, refer

https://brainly.com/question/24430414

#SPJ2

why does apparent depth of different liquids vary

Answers

It’s due to the refraction of light rays as they traverse the boundary between water and air. The greater the viewing angle, the more the bending of the light and therefore the less the apparent depth. An object placed in a denser medium, when viewed from rarer medium appears to be at a lesser depth than its real depth due to refraction of light.
Other Questions
The core of transformer is laminated.......a.to reduce the loss of energy in the form of heat across the transformerb.to reduce the voltage of ACc.to decrease the voltage of ACd. to change the maginetic flux On the leeside of mountains, bands of heavy snow in some areas with trace amounts of snow in between is likely the result of: what the mining of althoe[tex]y \geqslant 3[/tex] Which classification best represents a triangle with side lengths 6 cm, 10 cm, and 12 cm?acute, because 62 + 102 < 122acute, because 6 + 10 > 12obtuse, because 62 + 102 < 122obtuse, because 6 + 10 > 12 Self-esteem and loss of control are keyfactors of our mental well being.A-TrueB-False Usually, in organizations, the policy and mechanism are established by the:CEOTeam of ExectivesBoard of DirectorsStakeholdersnone of these Describe the rights the roman republic gave its citizens. How similar are these rights to those given to citizens of the Islamic Republic of Pakistan? How did slavery function as a mechanism of racialized social control? I need to find evidence and analysis The dimensions of a closed rectangular box are measured as 60 centimeters, 50 centimeters, and 70 centimeters, with an error in each measurement of at most 0.2 centimeters. Use differentials to estimate the maximum error in calculating the surface area of the box. Find the value of x.A. About 57.6B. About 42.6C. About 12.6D. About 27.6 In the context of applications of artificial intelligence (AI), _____ perform well at simple, repetitive tasks and can be used to free workers from tedious or hazardous jobs. In which of the following cases is the Supreme Court most likely to rule that a person is simplyexercising freedom of speech and cannot be censored?-None of these choices are correct.-A former employee angry at being fired, publishes a blog falsely accusing hisformer boss of mistreating employees in an effort to get her fired-A college student writes an opinion piece for his school newspaper detailingareas in which he feels the national government needs improvement.-A member of the U.S. military opposes a war, so she leaks classified information on troop movements to the press.-A politician lies to voters in order to get elected According to _____ prayers said in company of others were _____ times more effective than what is said in private. * Which best describes the Democratic Party in the 1800's Look the phtoin the reply need 4 paragraphs in prg 1 : outline laras problem2:ask lara to think more carefully about the situation3: offer advice to make the friendship work4: tell him to speak to others about his problemplz plz helpp mee asap i will give more points and brainliest You are at a restaurant with a group of friends. Everyone else is ordering burgers and fries. You decide that you will order a hamburger, but you want to make a healthier choice than your friends.Which strategies could you use to make your food choice healthier? Select three options.Choose ketchup, mustard, or relish instead of mayonnaise.Order a healthy side dish.Ask for an extra large order of fries.Eat a smaller portion.Order bacon as a topping to increase the amount of protein. How does government support communities affrcted by gender based violence Factors that could affect the current oxygen and carbon dioxide levels? While youre on exchange in Guatemala, your parents come to visit and offer to take you and your host family out to eat.Given that your mother doesn't eat meat except for fish, which of the menu items listed above should she NOT order?1234*Note: This is a practice activity. Completing this activity will not only prepare you for future tests and assessments but, more importantly, it will enhance your understanding of Spanish culture. This activity will not count towards your grade. Variables, in statistics, refer to: A) characteristics of experimental unitsB) data that has been collectedC) unknown quantaties