Answer:
Positives (advantages) of Friction:
Friction is responsible for many types of motion -
It helps us walk on the groundBrakes in a car make use of friction to stop the carAsteroids are burnt in the atmosphere before reaching Earth due to friction.It helps in the generation of heat when we rub our hands.Negatives (disadvantages) of Friction:
Friction produces unnecessary heat leading to the wastage of energy.The force of friction acts in the opposite direction of motion, so friction slows down the motion of moving objects.Forest fires are caused due to the friction between tree branches.A lot of money goes into preventing friction and the usual wear and tear caused by it by using techniques like greasing and oiling.A scientist is examining an unknown solid. Which procedure would most likely help determine a chemical property of the substance?
heating it to find the temperature at which it melts
exposing it to a flame to see if it catches on fire
hitting it with a hammer to determine if it breaks or bends
placing it in water to find out whether or not it dissolves
Answer:
hitting it with a hammer to determine if it breaks or bends
Answer:
exposing it to a flame to see if it catches on fire
Explanation:
A chemical property is when the matter changes into a different substance. This is true when you expose it to a flame because if a substance is burned, it will change into a new substance. All the other options are examples of physical changes.
-I also took the quiz and got 100%
Hope this helps!
how big is omniverse?
Answer:
big half like whale is so big
For every action, there is an equal and opposite reaction.
Does the statement describe a scientific law?
Answer:
This is newton's 3rd law
Explanation:
a hotgas is injected into at engine at 573 k and exhausts at 343 k. what is the highest efficiency of thisengine?
Answer:
230k
Explanation:
energy capacity maximum is 573 total available. 343k of that energy is present at release and subsequent loss leaving max used energy of 230k.
Why are circuit breakers and fuses important?
1)They help regulate the voltage drop in a power source.
2)They help insulate live wires to prevent shocks.
3)They help prevent electrical accidents.
4)They help current flow smoothly.
Answer:
option 3, as circuit breakers are mostly used as precautions
how can you reduce output voltage to 6v in transformers if the input voltage is 240v
Answer:
[tex]N_P = 40\ N_S[/tex]
To reduce the output voltage to 6v in transformers if the input voltage is 240v, we need to have 40 times as many turns in the primary coil as there are in the secondary coil.
Explanation:
The change in voltage of a transformer depends upon the turns ratio of the transformer between secondary and primary coil. Following formula can be used to determine the turns ratio in this case:
[tex]\frac{N_P}{N_S} = \frac{V_P}{V_S} \\\\[/tex]
where,
[tex]N_P[/tex] = No. of turns in the primary coil
[tex]N_S[/tex] = No. of turns in the secondary coil
[tex]V_P[/tex] = voltage in the primary coil = 240 V
[tex]V_S[/tex] = voltage in the secondary coil = 6 V
Therefore,
[tex]\frac{N_P}{N_S} = \frac{240\ V}{6\ V} \\\\N_P = 40\ N_S[/tex]
To reduce the output voltage to 6v in transformers if the input voltage is 240v, we need to have 40 times as many turns in the primary coil as there are in the secondary coil.
give reason for the following observation
The smell of hot sizzling food reaches you several metres away but to get the smell from cold food you have to go close.
Answer: The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close because the kinetic energy of the particles of matter increases with the increase in temperature. In cold foods, kinetic energy is less while in hot foods, kinetic energy is more
hope this helps
Smell spreads due to diffusion. In hot food the molecules have a lot of kinetic energy , and they therefore spread fast , whereas in cold food the kinetic energy of the molecules are less and they don't spread far.
A person walks at a speed of 6 km/h from point A to point B. If he improves his pace by 1.5 km/h, he will arrive 1 hour earlier.
a) calculate the distance and time he intends to travel from a to b
b) the individual initially travels at v1=6 km/h for a distance s1, then pauses for 15 minutes to rest. So he goes at v2=7.5km/h for the rest of the route and arrives 30 minutes early than expected.
Answer:
a) The distance is 30 km
The time duration is 5 hours
b) s₁ is approximately 28.142 km or s₁ is approximately 1.505 km
Explanation:
The initial speed with of the person, v₁ = 6 km/h
The distance the walked by the person, d = From point A to point B
The rate at which the person increases the speed, Δv = 1.5 km/h
The time it takes for the person to arrive at point B from point A at the new speed, t₂ = 1 hour earlier than when walking at 6 km/h
a) Let t₁ represent the time it takes the person walking from point A to point B at 6 km/h, we have;
t₂ = t₁ - 1...(1)
d/t₁ = 6...(2)
d/t₂ = 6 + 1.5 = 7.5
∴ d/t₂ = 7.5...(3)
From equation (2), we have;
d = 6 × t₁ = 6·t₁
Plugging in d = 6·t₁, and t₂ = t₁ - 1 in equation (3) gives;
d/t₂ = 7.5
∴ 6·t₁/t₁ - 1 = 7.5
6·t₁ = 7.5 × (t₁ - 1) = 7.5·t₁ - 7.5
7.5·t₁ - 6·t₁ = 7.5
1.5·t₁ = 7.5
t₁ = 7.5/1.5 = 5
t₁ = 5
The time it takes the person walking from point A to point B at 6 km/h, t₁ = 5 hours
The distance from point A to point B, d = 6 km/h × 5 hours = 30 km
b) The distance the person travels at the initial speed, v₁ (6 km/h) = s₁
The duration the person pauses for a rest = 15 minutes = 1/4 hours
The speed with which he walks the rest of the journey, v₂ = 7.5 km/h
The time earlier than expected that he arrives, Δt = 30 minutes = 0.5 hours
We note that the total distance, d = 30 km
The expected time, t₁ = 5 hours
Therefore, we have;
s₁ + s₂ = 30 km
s₂ = 30 - s₁
v₁/s₁ + 1/4 + v₂/s₂ = t₁ - 0.5
Therefore;
6/s₁ + 1/4 + 7.5/(30 - s₁) = 5 - 0.5 = 4.5
6/28.142+ 1/4 + 7.5/(30 - 28.142) = 5 - 0.5 = 4.5
6/s₁ + 7.5/(30 - s₁) = 4.5 - 1/4 = 4.25
-(3·s₁ + 360)/(2·s₁²- 60·s₁) = 4.25
2·s₁²- 60·s₁) × 4.25 + 3·s₁ + 360 = 0
17·s₁²- 504·s₁ + 720 = 0
s₁ = (504 ± √((-504)² - 4 × 17 × 720))/(2 × 17)
s₁ ≈ 28.142 or s₁ = 1.505
The distance the individual travels at v₁ = 6 km/h, s₁ ≈ 28.142 km or 1.505 km
Lucas pushes on a car stuck in a ditch with a force of 1000 N for 15 minutes. The car remains stuck. How much work did Lucas do?
Your answer:
O 66.7)
0 0
o 1.22)
O 22,000
Answer:
I think it would be the second answer...
Explanation:
Hope this helps!
Lucas do a work of 0 joule. Hence, option (B) is correct.
What is work?The notion of work in science is significantly different from what it is understood to entail in ordinary life. Every time work is performed, energy is transmitted, as shown by the definition of work in physics.
A force must be applied and there must be movement in the force's direction for a work to be completed scientifically. Having said that, we may state that The product of the component of the force acting in the displacement's direction and its magnitude is work.
Mathematically work done can be expressed as:
work done = force × displacement × cosθ
Where θ is the angle between the force and the displacement .
Here, the car remains stuck, that means, no displacement happens. So. Lucas do a work of 0 joule.
Learn more about work here:
https://brainly.com/question/19382352
#SPJ6
The total momentum before a collision is___to the total momentum after a collision
Answer:
Equal
Explanation:
The law of conservation of energy states that the total momentum before and after a collision are equal
Answer:
Equal to the total momentum of the two objects after the collision.
The process of making alloys involves
Answer:
The process of making alloys involves ( Heating ) pure metals to remove impurities. Then the pure metals are(mixed) with other components. An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by a metallic bonding character.
Explanation:
1. 10. waves break on the beach in 2.0 min. What is the frequency in hertz of these waves (cycles per
second)? What is the time between successive waves, in seconds?
Answer:
there it is fella tried o. ma own consciousness
6. A ball rolled 125 m from the top of a hill to the bottom of a hill. How long
did it take for the ball to roll if the average velocity was 5m/s? *
Select all the correct answers. Which statements about potential energy are true?
Answer: The statement gaining potential energy is always associated with a force field, is true about potential energy.
Explanation:
The energy acquired by an object due to its position is called potential energy.
Basically, a force field exerts a force that gives rise to potential energy of an object. For example, gravity, spring force etc.
This means that gaining potential energy is always associated with a force field.
A change in position does not always means that an object gains potential energy. For example, a spring will have more potential energy when it is compressed or stretched.
Hence, change in position of an object not necessarily means always gain in potential energy.
There are two types of potential energy that is, gravitational potential energy and elastic potential energy.
Thus, we can conclude that the statement gaining potential energy is always associated with a force field, is true about potential energy.
Answer:
Explanation:
The first one and the last one are the correct answer.
An object falling straight down without air resistance is said to be exhibiting
A. free fall
B. projectile motion
C. circular motion
D. two-dimensional motion
Answer:
Explanation:
If the object is falling straight down it is in free fall. The difference between that and two-dimensional motion is that 2D motion is parabolic (projectile)
Sound travels slowest through gases _____________________. Group of answer choices because the molecules of gas are close together because gases are air because the molecules of gas are far apart because gases have the lowest temperature
A riddle for you
In some situations, I oppose the motion
in other situations, I facilitate the motion
but, I always oppose
the relative motion
between two moving surfaces.
Put some lubricant, and
I become small there.
Make the moving surfaces rough
I make the movement tough.
I may be
static, sliding or rolling
but whenever two surfaces are in motion
I am always there,
Tell me who I am!
The person who answers it correctly will be marked as brainlist
Answer:
The Answer is FRICTION!
A CAR APPROACHING A SCHOOL ZONE SLOWS DOWN FROM 38 M/S TO 10 M/S AT A CONSTANT ACCELERATION -4 METER PER SEC SQUARE HOW MUCH TIME IS REQUIRED TO SLOW DOWN TO FINAL VELOCITY
Answer:
7 seconds
Explanation:
he went down -28 m/s so 7 times -4 equals -28 m/s which is what he needed to slowness down to 10 m/s
Discuss how our lives on Earth are directly related to our relationship and positioning with the Sun in our Solar System.
Answer:
They are because 1. New years culture benefits 2. Gives the right amount of heat as well as a day/ night cycle and the 4 seasons because of the earths tilt
Answer:
Explanation:
Our lives on earth are directly connected to the sun and our solar system because they give the right amount of heat and as well as the day and night cycle. Furthermore, due to the earth’s tilt, we get our four seasons which are very important to us as humans, getting different seasons and weather conditions.
The solar system also affects the tides and
A Long time ago, the Moon was closer to the Earth and spinning rapidly. The Moon’s tidal bulges didn’t align with the Earth, and the Earth’s gravity tugged on them, slowing the Moon’s spin and moving it farther away. As it moved farther away, the time it took to orbit once around the Earth increased: Its orbital period got longer. Eventually, the lengthening rotation of the Moon matched how long it took to go around the Earth. When that happened, the axis of the bulges pointed right at the Earth. That’s why the Moon only shows one face to us! It spins once per month and goes around us once per month.
Gravity is a force, and it weakens with distance. An important thing to note is that we measure gravity from the center of mass of an object, not its surface. One way to think of the center of mass of an object is the average position in an object of all its mass. For an evenly distributed sphere, that’s its center.
Since gravity weakens with distance, the force of Earth’s gravity on your head is less than it is on your feet, it’s way too small for you to ever notice. This change in the force of gravity over distance is what astronomers call the tidal force. The overall effect of the tidal force is to stretch an object.
The Moon has gravity. Just as the bulge is pulling the Moon ahead, the Moon is pulling the bulge back, slowing it down. Because of friction with the rest of the Earth, this slowing of the bulge is actually slowing the rotation of the Earth itself, making the day longer. The effect is small, but it’s measurable.
The constellations and astronomy give us our zodiac signs, and from previous knowledge, I know that zodiac signs impact our personalities greatly. If constellations were not found then zodiac signs wouldn’t have been created.
PLS HELPP HURRYYY
The trapdoor swings open and the ball falls to the ground. The ball does not bounce when it hits the ground. Show that the final speed of the ball at the instant before it hits the ground is about 5 m/s.
Answer:
5 m/s
Explanation:
As the ball falls to the ground, it is acted upon by a force which is due to the gravitational force. Hence, the ball falls with an acceleration called the acceleration due to gravity.
Let us assume that the acceleration due to gravity (g) = 10 m/s², Since initially, the body was at rest, hence the initial velocity (u) = 0 m/s. The height to the ground (h) = 1.3 m. Hence using the equation of motion, the final velocity (v) is:
v² = u² + 2gh
Substituting:
v² = 0² + 2(10)(1.3)
v² = 26
v = √26 = 5
v = 5 m/s
A 8.6*10^ -6 C charge is places 1.00 m away from a 2.3 * 10 ^ - 4 * C charge. How large is the force of repulsion between the two charges?
Answer:
The force of repulsion is 17.802 N
Explanation:
Given;
magnitude of the first charge, q₁ = 8.6 x 10⁻⁶ C
magnitude of the second charge, q₂ = 2.3 x 10⁻⁴ C
distance between the two charges, r = 1 m
The force of repulsion is calculated using Coulomb's law;
[tex]F = \frac{Kq_1q_2}{r^2} \\\\F = \frac{9\times 10^9 \times 8.6\times 10^{-6} \times 2.3\times 10^{-4}}{1^2} \\\\F = 17.802 \ N[/tex]
Therefore, the force of repulsion is 17.802 N
Pascal in term fundamental unit is?
Answer: SI unit of pressure
Explanation: The pascal (pronounced pass-KAL and abbreviated Pa) is the unit of pressure or stress in the International System of Units (SI). Reduced to base units in SI, one pascal is one kilogram per meter per second squared; that is, 1 Pa = 1 kg · m-1 · s-2.
Hope this helps! Have a fantastic rest of ur day, luv!
Which property of the coating on fiber-optic strands makes light visible only at the ends of the strands?
reflectivity
absorbency
transparency
translucency
The answer is A, Hope this helps and sorry for being late :)
man start to moves from point A (Initial Point) to Point B (Final Point) in a given
figure. Find the Distance and Displacement from the given Figure :-
(2)
Answer:
Image not full.
Explanation:
From what I can see, Displacement is 175m,
Distance will be = 100 + 50 + the hidden value on the bottom right
I need help pleaseee
Answer:
a refraction
b reflection
creflection
d refraction
brainliest plzz
Si un automóvil logra una potencia util promedio de 250kw y se sabe que tiene un rendimiento energético del 25%. ¿Cuanta energia total consume en 1 min? Exprese el resultado en kj
Answer:
W = 3.75 kJ
Explanation:
Power is defined by the relational
P = W / t
W = P t
the yield is 25% = 0.25
W = 0.25 Wo
W = 0.25 250 60
W = 3750 J
W = 3.75 kJ
Find the force due to a current element of length 6cm and flux density of 12 tesla. The current through the element will be 10A.
Answer:
7.2 N
Explanation:
Applying,
F = BIL................. Equation 1
Where F = Force due to current through the element, B = magnetic field, L = Length of the element.
From the question,
Given: B = 12 Tesla, L = 6 cm = 0.06 m, I = 10 A
Substitute these values into equation 1
F = 12(0.06)(10)
F = 7.2 N
Hence the force through the element is 7.2 N
(02.06)plz help me 20 points
Answer:
the answer is 80 degrees
Explanation:
A 91.5 kg football player running
east at 2.73 m/s tackles a 63.5 kg
player running west at 3.09 m/s.
What is their velocity afterward?
Answer:
I'm pretty sure the velocity is 2.88 m/s
Explanation:
hope this is right good luck
Answer:
0.348
Explanation:
Acellus
A _____ is a model of an atom in which each dot represents a valence electron
Answer:
electron dot diagram is the answer to your question.
