Answer:
Positive work is said to be done when the force acting on a body produces a displacement in the direction of the force. Negative work is said to be done when the force acting on a body produces a displacement opposite to the direction of the force
Explanation:
When the displacement of the body the in the direction of the force then the work done is positive. For example :- a man pushing a car in a straight path.
When the displacement is in a direction opposite to the direction of the force then the work done is said to be negative. For example :- work done by the friction.
Calculate the number of moles in 44 g of iron sulfide.
Relative atomic masses
(4): Fe = 56, S = 32
Answer:
2 moles
Explanation:
please mark me as brainlest
The mass of one mole of iron sulphide is 88 g. Then the number of moles in 44 g is 0.5 moles.
What is one mole ?One mole of a substance is its amount which contains 6.022 × 10²³ atoms. This number is called Avogadro number. One mole of every element contains Avogadro number of atoms.
Similarly one mole of every compound contains Avogadro number of molecules. The mass of one mole of a compound is called its molar mass.
Atomic mass of Fe = 56 g/mol
atomic mass o S = 32 g/mol
molar mass of FeS = 56 + 32 = 88 g/mol
Mass of one mole of iron sulphide (FeS) is 88 g. Hence number of moles in 44 g is :
no.of moles = given weight/molar mass
= 44 g /88 g/mol = 0.5 mol
Therefore, the number of moles of FeS in 44 g is 0.5.
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The temperature below which magnetic material can retain a permanent magnetization is called the ________. Group of answer choices Bullard point Darcy temperature Vine temperature Curie point
Answer: Your answer is D. Curie point
Hope this helps!
Which of the following is not a type of friction
a
static
b
sliding
c
rolling
d
fluid
e
gravitational
Answer:
Fluid (d).
Explanation:
When there is fluid, there can't be friction.
In a science lab, Cash mixes two clear liquids together in a beaker. Bubbles are produced, and a white solid forms and settles to the bottom. He plans to heat the beaker over low heat and make more observations.Which statement is most likely correct? A physical change occurred, so if Cash heats it, the white solid will dissolve to form the original mixture of clear liquids. A physical change occurred, so even if Cash heats it, the white solid will remain. A chemical change occurred, so if Cash heats it, the white solid will dissolve to form the original mixture of clear liquids. A chemical change occurred, so even if Cash heats it, the white solid will remain.
Answer:
A chemical change occurred, so even if Cash heats it, the white solid will remain
Explanation:
There are two types of changes that occur in Chemistry viz; physical change and chemical change. Physical changes are those changes do not involve any change in the chemical composition of the substances involved while a chemical change involves a change in chemical composition.
In a chemical change, there are characteristics signs such as formation of gaseous bubbles, solid precipitates etc. as the information in this question depicts. According to this question, Cash mixes two clear liquids together which results in the formation of bubbles and a white solid that settles at the bottom. Hence, THIS REPRESENTS A CHEMICAL CHANGE
Most chemical changes are usually irreversible i.e. they don't return to their original form. Hence, even if Cash heats it, the white solid will remain.
Answer:
A chemical change occurred, so even if Cash heats it, the white solid will remain
True or False:
Solids always
have a higher density than
liquids and gases.
Answer:
False I hoped this helpful for you....Thank you ☺️☺️
Answer:
True.
Explanation:
This is because the solid particles are very close to each other due to strong intermolecular force attraction between them.
a) On which hemisphere does Bhutan lie on the earth?
Answer:
Northern Hemisphere
Explanation:
The latitude of Bhutan is 27.5142° N, placing the country in the northern hemisphere above the equator
A box falls off of a tailgate and slides along the street for a distance of 62.5 m. Friction slows the box at –5.0 m/s2. At what speed was the truck traveling when the box fell?
Answer:
25 m/s
Explanation:
This question can be solved using equation of motion
[tex]v^2 = u^2 + 2as[/tex]
where
v is the final velocity
u is the initial velocity
s is the distance covered while moving from initial to final velocity
a is the acceleration
_____________________________________________
Given
box moved for distance of 62.5 m
Friction slows the box at –5.0 m/s2----> this statement means that there is deceleration , speed of truck decreases by 5 m/s in every second until the box comes to rest. Friction causes this deceleration.
thus in this problem
a = -5.0 m/s2
V = 0 as body came to rest due to friction deceleration
u the initial velocity we have to find
the initial velocity of box will be the same as speed of truck, as the box was in the truck and hence box will pick the speed of truck.
so if we find speed of box, we will be able get sped of truck as well.
using equation of motion
[tex]v^2 = u^2 + 2as\\0^2 = u^2 + 2*-5* 62.5\\0 = u^2 - 625\\u^2 = 625\\\sqrt{u^2} = \sqrt{625} \\u = 25[/tex]
Thus, initial speed with the truck was travelling was 25 m/s.
When a substance goes directly from a solid state to a gas state, as dry ice
does, ___
A. it's called deposition.
B. the line on the energy-vs. temperature graph is horizontal.
C. it's called sublimation.
D. it's undergoing a phase change.
E.it's called fusion.
it's called sublimation
Explanation:
it's called sublimation.
Which of the following is true about metabolism
Your metabolism speeds up naturally as you get older
You can never speed up or slow down your body’s metabolism
Your basal metabolism is the amount of energy (calories) your body uses just to keep you living
Your metabolism is not affected your heredity, age and maturation
An object of mass 2 kg rests on the floor, as shown in the picture. A force of 45 N, making an angle of 60° to the vertical, is applied
to move the object. What is the acceleration of the object in the horizontal direction?
Answer:B
Explanation:
I just did that
Jim and Harry are having a race to get to Cindy's house. Cindy's house is 600 meters away. Jim runs as hard as he can with a speed of 5.3 m/s and Harry jogs with a speed of 8.2 m/s. How long will Harry have to wait for Jim when he gets to Cindy's house?
Given :
Cindy's house is 600 meters away. Jim runs as hard as he can with a speed of 5.3 m/s and Harry jogs with a speed of 8.2 m/s.
To Find :
How long will Harry have to wait for Jim when he gets to Cindy's house.
Solution :
Time taken by Harry to reach Cindy's house :
[tex]t_1=\dfrac{600}{8.2}\ s= 73.17\ s[/tex]
Time taken by Jim to reach Cindy's house :
[tex]t_2=\dfrac{600}{5.3}\ s=113.21\ s[/tex]
Time taken by Harry to wait for Jim is :
T = [tex]t_2-t_1[/tex] = 113.21 - 73.17 s = 40.04 s
Hence, this is the required solution.
A block is at rest on a frictionless ramp that is elevated 22.0 degrees above the horizontal.
a)Determine the acceleration of the block as it slides down the ramp.
Answer:
3.67 m/s²
Explanation:
Draw a free body diagram. There are two forces on the object:
Weight force mg pulling straight down,
and normal force N pushing perpendicular to the plane.
Sum the forces in the parallel direction.
∑F = ma
mg sin θ = ma
a = g sin θ
a = (9.8 m/s²) (sin 22.0°)
a = 3.67 m/s²
A positive charge moving up enters a magnetic field pointing out of the screen. What is the direction of the magnetic force on the charge?.
Answer:
y5
Explanation:
The magnetic force is perpendicular to the velocity and the magnetic field. The direction of the magnetic force can be determined using the right-hand rule, putting the fingers of the right hand in the direction of the velocity and curl your fingers or roll them in the direction of the magnetic field. The thumb gives the direction of the magnetic force. If the charge is negative, the direction of the force is opposite to the result obtained using the right-hand rule.
The direction of a moving charge's magnetic field lines is always perpendicular to the plane created by velocity and magnetic force.
If the positive charge is moving upwards the corresponding current is also upwards, the magnetic field is towards the south.
What is magnetic force ?"Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. It is the basic force responsible for such effects as the action of electric motors and the attraction of magnets for iron."
What is magnetic field ?"The magnetic field is the area around a magnet in which the effect of magnetism is felt. We use the magnetic field as a tool to describe how the magnetic force is distributed in the space around and within something magnetic in nature."
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how long does it take a car to come to a complete stop if it is going 30 m/s and can accelerate at a rate of -6 m/s²?
Answer: t=10s
Explanation:
v=u+at
⟹0=30+(−3)×t
⟹0=30−3t
⟹3t=30
⟹t=303
⟹t=10s.
how does a aircraft become charged as it fly
Answer:
Precipitation static is an electrical charge on an airplane caused by flying through rain, snow, ice, or dust particles. Charge also accumulates through friction between the aircraft hull and the air. When the aircraft charge is great enough, it discharges into the surrounding air.
Explanation:
I hope this helps!
Arrange the rock layers from oldest to youngest. Reexamine the rock outcrops if you need to. Record the order in the
Student Guide.
TOOLS
youngest
Breccia
Conglomerate
Age
Dolostone
Shale
oldest
Answer:
from top (youngest) to bottom (oldest) -
Conglomerate
Brecca
Shale
Dolostone
Explanation:
got it wrong from the person above and then it said this the right answer lol.
The oldest rock layer among the given options is shale then it is dolostone and then conglomerate and the youngest rock layer is Breccia.
What is sedimentary rocks?Sedimentary rocks are formed from the sediments by river and ocean. These are developed over time by the action of wind and water. Sedimentary rocks are deposition or accumulation or minerals on the earth surface.
There are different types of rock layers based on the minerals present, age and formation.Shale rock is a clastic sedimentary rock formed flakes of clay minerals.
Conglomerate rocks is another clastic rock containing round clasts of more than two millimeters in diameter. Dolostone or dolomite is limestone and breccia is a mineral cement with fine sharp angled fragments.
The oldest among this is shale and the order for others from oldest to youngest is dolostone, conglomerate and breccia.
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16 points and brainiest whoever is right
Two identical springs are dangling from the ceiling. The first spring is pushed upward with a
force of magnitude 188 N, compressing the spring by 21.8 cm. A box of weight 38 N is
attached to the end of the second spring. What distance is the second spring stretched?
please help me find the answer to this!
Question: Only one circuit below will light the bulb. Which one will work?
1.) A
2.) B
3.) C
4. D
thank you!
Grade: 6
Subject: Science
Answer:
C
Explanation:
The base of the lightbulb should touch the positive end and also the negative end of the battery.
find the force required to produce iacceleration of 2 metre per second square on a body of mass 10 kg what will be its acceleration if a force is double
The wording of the problem leaves much to be desired. It does not indicate in which direction is the object’s acceleration. It also fails to mention the presence or absence of friction. In order to cover all conditions, the answer must be a range of values, with the direction changing from zero to ninety degrees.
The range would be: 20 N to 120 N (100 + 20 = 120) starting from zero all the way up to ninety degrees.
Hope it Helps❤what’s the frequency of the wave?
are you in kindergarten
Phenomena that Occur on the Surface of the Sun
please help me asap. and please label it. thank youuu !
Answer:
solar wind
radio wave plux
solar flares
coronal mass ejections
coronal heating
Which force is responsible for determining the shapes of galaxies?.
Answer:
Gravity
Explanation:
Gravity is what causes stars to form. During accretion, gravity pulls matter into a core, which can be a star, planet or black hole.
Hi, please help me I need help.
Explanation:
Trains that use magnetic levitation (maglev) are suspended above the track, which greatly reduces friction from the rails and allows the trains to travel between 250 and 300 miles per hour! Magnetic levitation uses attractive and repulsive magnetic forces to suspend and control the speeds and motion of the trains.
Wich part of the brian helps you keep balance so you don't fall flat on your face?
A.Pituitaly glad
B.Medlla obonhata
C.Cerebellum
D.spinal cord
Answer:
Cerebellum .
Explanation:
The Cerebellum is the part of the brain that controls your walking and balance. If you need any more help feel free to reach out!
help in my home work!
convert 80°c to fahrenheit?
Answer:
176 degrees fahrenheit
Explanation:
80°C × 9/5) + 32 = 176°F
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80 °C
to find:80 °C as Fahrenheit
solution:[tex]f = (c \times \frac{9}{5} ) + 32[/tex]
[tex]f = (80 \times \frac{9}{5} ) + 32[/tex]
[tex]f = 176 \: fahrenheit[/tex]
hence, 80°C converted to Fahrenheit is 176°F
a car is moving at 30.0 km/h when it accelerates at 2.0 m/s for 3.6 s. what is the car final speed?
Answer:
wrong question
Explanation:
unit of acceleration is written in m/s which is wrong
The final velocity of the car which is moving with the initial velocity of 30km/h is 15.53m/s.
What is Acceleration?Acceleration of an object is the rate of change in the velocity of an object. It depends upon the initial and final velocity of an object. It is a vector quantity because it has both magnitude and direction. The SI unit of acceleration is meter per second square.
a = (v-u)/ t
v = u + at
u = 30 × 1000/ 3600 = 8.33m/s
a = 2.0m/s²
t = 3.6 seconds
v = u + at
v = 8.33 + 2.0 × 3.6
v = 8.33 + 7.2
v = 15.53m/s
Therefore, the final velocity of the car is 15.53m/s.
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Is cereal soup? Why or why not? Pls HELP ASAP
Answer:
yes
Explanation:
by definition, yes. soup is defined as "a liquid dish, typically made by boiling meat, fish, or vegetables, etc., in stock or water.", so a liquid dish prepared by boiling and extracting flavor. so technically, a bowl of cereal would be a wheat-milk soup.
Which is true of high resistance wires?
A. The longer the wire the higher the resistance.
B. The shorter the wire the higher the resistance.
C. The longer the wire the lower the resistance.
Why do you build up a static charge when you rub your shoes across the carpet?.
The rubbing of certain materials against one another can transfer negative charges, or electrons. For example, if you rub your shoe on the carpet, your body collects extra electrons.
__________ is the most common type of stretching.
Answer: static stretching
Explanation:
e.g rubberband
Answer:
static stretching
Explanation: