Answer:
A person climbs a set of stairs
Explanation:
Potential energy is said to be possessed by an object due to its position. As the height from the ground level increase, the potential energy increases. It is calculated by the below formula as :
P = mgh
Out of the given options, the option that illustrates an increase in potential energy is option (b) i.e. a person climbs a set of stairs. As he steps one stair, its position from ground increases. It means its potential energy increases.
At summer camp, the swimming course runs the length (L) of a small lake. To determine the length of the course, the camp counselors measure the two "dry" legs of a right triangle. What is the length in meters of the swimming course in the figure below?
Answer:
47.17 m
Explanation:
From the diagram of the question attached, The length of the legs are 25 m and 40 m . This legs form a right angle triangle with the length of the swimming course (L).
Pythagoras theorem states that for a right angle triangle with hypotenuse a and legs b and c, then:
a² = b² + c²
In the triangle, the length of the swimming course (L) is the hypotenuse and the two legs are 25 m and 40 m. Using Pythagoras:
L² = 25² + 40²
L² = 625 + 1600
L² = 2225
L = √2225
L = 47.17 m
Calculate the volume of this regular solid. A cylinder labeled B at the top, 13 centimeters high with a radius of 4 centimeters. What is the volume of the cylinder? Round your answer to the nearest hundredth.
Answer:
The volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]
Explanation:
Given that,
The height of the cylinder is 13 cm
Radius of the cylinder is 4 cm
We need to find the volume of the cylinder. The formula that is used to find the volume of a cylinder is given by :
[tex]V=\pi r^2 h\\\\V=\dfrac{22}{7} \times (4)^2 \times 13\\\\V=653.71\ \text{cm}^3[/tex]
So, the volume of the cylinder is [tex]653.71\ \text{cm}^3[/tex]
Answer:
653.45 is the answer
Explanation:
A person holds a 25 kg (250 newton) bag of cement over his head and moves it a distance of 10 m, taking 2 minutes, while another person carries it on a wheelbarrow that same distance, taking 1 minute.Who does more work ? What is the power of each person?
Explanation:
Assuming the 10 m distance is the vertical displacement, the work done by both people is the same.
Work = force × distance
W = (250 N) (10 m)
W = 2500 J
The power of the first person is:
Power = work / time
P = 2500 J / 120 s
P = 20.83 W
The power of the second person is:
P = 2500 J / 60 s
P = 41.67 W
Un pez llamado PARGO ROJO vive a grandes profundidades. Si se pesca, al salir a la superficie puede tomar el aspecto de la foto porque su vejiga natatoria aumenta de volumen al disminuir la presión. La ley que lo explica es...
Answer:
Hay diversas leyes que podemos usar acá.
Acá sabemos que la vejiga aumenta su tamaño al reducir la presión, esto tiene sentido, pues al haber menos presión, hay menos fuerza que comprime la vejiga, lo que le permite aumentar su volumen.
Acá tenemos una relación inversa de la forma: V = K/P
Una relación inversa donde la presión esta en el denominador y K es un termino que no depende ni del volumen ni de la presión.
Entonces, a medida que aumenta P, el denominador aumenta, por lo que el valor del volumen decrece.
Un ejemplo de una ecuación similar es la del gas ideal, por ejemplo, para un gas ideal dentro de un globo de volumen V para una dada presión P:
V = nRT/P
donde n es el numero de moles, R es la constante termodinámica y T es la temperatura, acá podemos ver que esta ecuación tiene la misma forma fundamental que la escrita arriba.
explain why the density of a gas is much less than that of a solid or liquid
Answer:
A gas usually has much lower density than a solid or liquid. ... The molecules or atoms in a gas are much further apart than in a solid or a liquid. Gas molecules or atoms are usually flying around at very high speeds, occasionally bouncing off each other or the walls of the container the gas is in.
when you turn on music on your phone, what energy transformation takes place ?
Answer: A Battery contains chemical energy which transfers electrical energy into the phone, powering it and also transferring Light energy, Sound energy and Heat energy.
Explanation:
Which example best describes a restoring force?
any force that is applied to a spring to change its length
the force applied to stretch a spring and increase its length
the force applied to restore a spring to its original length
the force applied to compress a spring and shorten its length
Answer:
the force applied to restore a spring to its original length
Explanation:
A container contains 200g of water at initial temperature of 30°C. An iron nail of mass 200g at temperature of 50°C is immersed in the water. What is the final water temperature? State the assumptions you need to make in your calculations.
[Given the value of specific heat capacity of water is 4200 J kg^-1 °C^-1 and that of iron is
450 J kg^-1 °C^-1]
Answer:
The final temperature is 31.94°
Explanation:
The mass of the water in the container m₁ = 200 g = 0.2 kg
The initial temperature of the water, T₁₁ = 30°C
The mass of the iron, m₂ = 200 g = 0.2 kg
The temperature of the iron T₂₁= 50°C is immersed in the water,
The specific heat capacity of the water, c₁ = 4200 J/(kg·°C)
The specific heat capacity of the iron, c₂ = 450 J/(kg·°C)
Heat capacity relation is given by the formula;
Heat capacity Q = Mass, m × Specific heat capacity, c × Temperature change, (T₂ - T₁)
Given that energy can neither be created nor destroyed, and with the assumption that all the heat lost by the nail is gained by the water we have;
Heat lost by iron nail = Heat gained by the water
m₁ × c₁ × (T₂ - T₁₁) = m₂ × c₂ × (T₂₁ - T₂)
Where, T₂ is the final temperature
0.2 kg × 4200 J/(kg·°C) × (T₂ - 30) = 0.2 kg × 450 J/(kg·°C) × (50° - T₂)
840·T₂ - 25200 = 4500 - 90·T₂
4500 + 25200 = 840·T₂ + 90·T₂
29700 = 930·T₂
T₂ = 29700/930 = 31.94°.
The final temperature = 31.94°.
If an object floats, the volume of the displaced water is equal to the volume of the whole object. True or false?
Answer:
True
Explanation:
This is in fact what the Archimedes principle states, and what he used in the famous anecdote about finding if the crown of the King was really made of gold.
1-A boy rolls a toy car across a floor with a velocity of 3.21 m/s. How long does it take the car to travel a distance of 4.50 m?
A-0.71s
B-1.40s
C-2.9s
D-14s
2-A girl heads out for a jog and runs at 2.95 m/s, due North, for 3600 s. How far did she run?
A-0.194 x 10^-4
B-1220m
C-5240
D-10620
3-A car is traveling South on I-85. It travels between two exits that are 5.40 km apart in 4.85 minutes. What is the average velocity of the car in m/s?
A-8.42m/s
B-12.8m/s
C-14.9m/s
D-18.6m/s
4-An airplane takes 1.30 hours to travel to an airport north of Atlanta. If the average speed of the plane is 134 m/s, what is the plane's displacement as measured from Atlanta?
A-129,324m=129,000m rounded
B-356,247m=356,000m rounded
C-498,782m=499,000m rounded
D-627,120m=627,000m rounded
5-How long does it take a sailboat traveling 18.0 m/s to go 15.7 km west?
A-15,000s
B-872s
C-594s
D-326s
what is the symbol of mecury
If you are talking about mecury as in a chemical element than it is: Hg
If you are talking about the planet Mercury than: The symbol for Mercury represents the head and winged cap of Mercury, god of commerce and communication, surmounting his caduceus (staff). The symbol for Venus is designated as the female symbol, thought to be the stylized representation of the hand mirror of this goddess of love.
Answer:
The symbol of mercury is....
Hydrargyrum ( Hg )
Hope this helps......
Pls mark my ans as brainliest
A wire of length 5mm and Diameter 2m extends by 0.25 when a force of 50N was use. calculate the
a. Stress of the wire.
b. Strain of the wire
Answer and Explanation:
Data provided in the question
Force = 50N
Length = 5mm
diameter = 2.0m = [tex]2\times 10^{-3}[/tex]
Extended by = 0.25mm = [tex]0.25\times 10^{-3}[/tex]
Based on the above information, the calculation is as follows
a. The Stress of the wire is
[tex]= \frac{force\ applied}{area\ of \ circle}[/tex]
here area of circle = perpendicular to the are i.e cross-sectional i.e
= [tex]\frac{\pi d^{2}}{4}[/tex]
= [tex]\frac{\pi(2\times 10^{-3})^2}{4}[/tex]
Now place these above values to the above formula
[tex]= \frac{4\times 50}{\pi\times 4 \times 10^{-6}} \\\\ = \frac{50}{\pi}[/tex]
= 15.92 MPa
As 1Pa = 1 by N m^2
So,
MPa = 10^6 N m^2
b. Now the strain of the wire is
[tex]= \frac{Change\ in\ length}{initial\ length} \\\\ = \frac{0.25\times 10^{-3}}{5}[/tex]
= [tex]5 \times 10^{-5}[/tex]
In series combination of resistors, the total electric current is equal to the current flowing through each resistor.
A. False B. True C.The statement above lacks information
WILL GIVE BRAINLIEST! :)
Answer:
The answer is B, true.
Because same current flows through each resistors in Series.
Plz Mark as Brainlist
And follow me.
[tex] \LARGE{ \underline{ \tt{ \pink{True \: or \: False}}}}[/tex]
The above statement is true.
❍ In series combination of resistors, the total electric current is equal to the current flowing through each resistor..
Explanation:-In series combination, the resistors are connected end to end.There is no branch of extra wire with resistor, Hence Current through the entire circuit remains constant.The Potential difference between the resistors changes due to variation in end points. The equivalent resistance of the total circuit is the sum of the resistors connected end to end.The total or equivalent resistance is always greater than other individual resistance.━━━━━━━━━━━━━━━━━━━━
an object weights 0.250 kgf in air 0.150 in water and 0.125 in an oil.find out the density of the object and the oil
Answer:
1) The density of the object = 2500 kg/m³
2) The density of the oil = 1250 kg/m³
Explanation:
1) The information relating to the question are;
The mass of the object in air = 0.250 kgf
The mass of the object in water = 0.150 kgf
The mass of the object in the oil = 0.125 kgf
By Archimedes's principle, we have;
The upthrust on the object in water = Mass in air - mass in water = The weight of the water displaced
The upthrust on the object in water = 0.250 - 0.150 = 0.1 kgf
∴ The weight of the water displaced = 0.1 kgf
Given that the object is completely immersed in the water, we have;
The volume of the water displaced = The volume of the object
The volume of 0.1 kg of water water displaced = Mass of the water/(Density of water)
The volume of 0.1 kg of water = 0.1/1000 = 0.0001 m³
The density of the object = (Mass in air)/ volume = 0.250/0.0001 = 2500 kg/m³
The density of the object = 2500 kg/m³
2) Whereby the mass of the object in the oil = 0.125 kgf
The upthrust of the oil = The weight of the oil displaced
The upthrust of the oil on the object = Mass of the object in air - mass of the object in the oil
The upthrust of the oil on the object = 0.250 - 0.125 = 0.125 kgf
The weight of the oil displaced = The upthrust of the oil
Given that the volume of the oil displaced = The volume of the oil, we have;
The volume of the oil displaced = 0.0001 m³
The mass of the 0.0001 m³ = 0.125 kg
Therefore the density of the oil = 0.125/0.0001 = 1250 kg/m³.
The density of the oil = 1250 kg/m³.
'When we see something that exists in real life, there are many different ways to display imagery and importance using art. What the artist _____________ depends on what he/she wants to communicate.'
Answer:
Emphasizes
Explanation:
The expression of an art is intelligible to those that understand it, as such to make an impression an artist has to emphasize the point they want to communicate
An art is an expression of the personal experiences of the artist or a reaction to events or to reveal the realities as seen by the artist such as global warming and the environment, so as to get the attention of people with the goal to change them, such that a good art changes the most people, hence the need for emphasis.
Answer:
A - emphasizes
A hammer is used to hit a nail into a board. Which statement is correct about the forces at play between the nail and the hammer? The nail exerts an equal force on the hammer in the same direction. The nail exerts a much smaller force on the hammer in the opposite direction. The nail exerts an equal force on the hammer in the opposite direction. The nail exerts a much smaller force on the hammer in the same direction.
Answer:
The nail exerts an equal force on the hammer in the opposite direction.
Explanation:
The Newtons third law states that there is an equal an opposite reaction for every action. When hammer pushes the nail, the nail will push the hammer back in opposite direction. When the hammer hits a nail then nail will exert the equal and opposite force to the hammer. These both objects will exert force on each other in opposite directions.
Hello, I am BrotherEye
Answer:
Answers are
1. "The nail exerts an equal force on the hammer in the opposite direction."
2. "500 N"
3. "The iron piece exerts a force of 1 N on the magnet in the opposite direction."
4. "When mass moves closer to the point of rotation, rotational inertia decreases."
5. "The skater spins slower because his rotational inertia has increased."
Explanation:
a bird statue with a mass 0.2 kg hangs from a rubber band with spring constant 30 N/m.How much is the rubber band stretched when the statue hangs motionless
Answer:
Distance : 0.06533 meters or 65.33 mm
Explanation:
To solve this problem we can make the forces equal when the system is at equilibrium.
mass [tex]*[/tex] gravity ( constant ) = spring constant
where l = the length at which the rubber band is stretched
0.2 kg [tex]*[/tex] 9.8 m / s² = 30 N/m
1.96 kg [tex]*[/tex] m / s² = 30 N/m
l = 1.96 kg [tex]*[/tex] m / s² / 30 N/m = 0.06533 meters / 65.33 mm
The rubber band is stretched a distance of 0.06533 meters, or 65.33 mm.
Answer:
0.065
Explanation:
Apex i just got it right
which of the following are possible units for a spring constant? A. N/nm B. nm/N C. nm/J D. J/nm
Answer:
Since N/m is the unit of spring constant N/nm would be the possible unit for a spring constant.
A. N/nm is the possible unit for a spring constant.
Is spring constant in N m?The units at the spring regular are Newton/meter (N/m). The poor signal within the above equation is an indication that the direction that the spring stretches is opposite the path of the pressure that the spring exerts.
Because the force is measured in Newtons and the spring consistent is multiplied with the aid of the gap in meters, the spring constant need to have devices that get rid of meters, ensuing most effective force. The most effective devices that work for the spring regular are for that reason, Newtons in step with the meter.
Learn more about spring constant here: https://brainly.com/question/1968517
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What happens when a sound wave passes from oil into air? A. the sound wave slows down and bounces back B. the sound wave slows down and bends C. the sound wave speeds up and bounces back D. the sound wave speeds up and bends
Oil is optically denser than water. When sound/light goes from optically denser medium to optically rarer medium, their velocity increase and they moves away for normal.
Appropriate Answer:The sound wave speeds up and bends
[tex] \Large{ \underline{ \boxed{ \pink{ \bf{Option \: (D)}}}}}[/tex]
As, In optics we learnt that light undergoes refraction when travels from medium of different densities. Similarly, Sound also follows the law of refraction.
It is due to the change of speed of water in different mediums, This makes it speed up or down depending upon the medium and their densities.━━━━━━━━━━━━━━━━━━━━
Answer:
the sound wave slows down and bends
Explanation:
a p e x
an astronaut takes a tuning fork with her to the moon she strikes it inside the cabin the cabin is normally filled with air so the humans inside the spacecraft are comfortable she also strikes it outside the spacecraft when she gets down on the surface of the moon which of the following is true about the tuning fork?
A: it does not vibrate inside the spacecraft
B: id does not vibrate on moon surface
C: it vibrations are not transmitted inside the spacecraft
D:it's vibrations are not transmitted to the moon's atmosphere
Answer:
The correct option is;
D: Its vibrations are not transmitted to the moon's atmosphere
Explanation:
A tuning fork is used to produce sound by vibration such that the tune produced is pure
The tune, sound, produced by the tuning fork is transmitted as sound wave through the air by means of the gases of the air as a transmission medium so people at a distance that have air around them can hear the tuning fork sound
On the Moon's surface, the atmosphere is very and it is referred to technically as an exosphere, so the sound of the tuning fork has no medium through which to transmit and therefore, it is not transmitted on the Moon's atmosphere.
what are some factors that affect the frequency of sound
Answer:
1. direction of propagation of sound
2.medium through which sound trsnsmitted
What areas of the work force can science be applied to?
Select all that apply
government regulatlon
healthcare
a telemarketing
environmental engineering
banking
Answer:
All of the work of lifeExplanation:
In all works of life science can be applied, in-fact science has already been applied already, even in the humanities, social sciences and art related studies sciences is being applied,
Furthermore, the application of science and technology knows no boundaries, and as science is advancing day by day, expanding to new frontiers and breaking new limits so is it application to all works of life and relevance everyday.
Using your own words, tell me
what is the difference between an Pure Substance and a Mixture? Make sure to give me an example of each.
Answer:
Hey there!
Mixtures are physically combined and can be separated. For example, sand and water is a mixture.
Pure substances are samples of matter with definite, and unchangeable chemical properties. For example, diamond is a pure substance.
Let me know if this helps :)
a pure substance is a substance that has not been mixed with anything, a mixture has been mixed with another substance. an example is
dirt +water=mud iron is an example of a substance
Please answer, it's really urgent A boy performs an experiment to measure the speed of sound. He stands 100 meters away form a large wall and claps his hands to make an echo. He claps again as soon as he was the echo, He does this ten times, each time clapping an soon as he hears the echo. The time between the first clap and the tenth echo a recorded. Why it better to time ten echoes together rather than just one echo?
Answer:
Explanation:
The speed of sound is very high . It is about 340 m /s . In one echo , it takes approximately
2 x 100 / 340
= .6 sec
In 10 simultaneous echo , it will take 6 s . It is difficult to measure .6 sec but to measure 6 s is easy and it can be made with greater precision , so we can calculate velocity of sound with great precision .
This is the reason why , instead of one echo , 10 echos are made and duration of 10 echo is measured , rather than making one echo and measuring time of one echo .
A car travels from point A to B in 3 hours and returns back to point A in 5 hours. Points A and B are 150 miles apart along a straight highway. Which of the following statements most accurately describes the motion of the car? Choose 1 answer:(Choice A) A The average velocity is 40 miles per hour. (Choice B) B The total displacement of the trip is 300 miles. (Choice C) C The average speed is 37.5 miles per hour. (Choice D) D The car travels at 50 mph for the first half and 30 mph for the second half.
Answer: D
Explanation:
Given that a car travels from point A to B in 3 hours and returns back to point A in 5 hours. Points A and B are 150 miles apart along a straight highway.
From point A to B
The speed = distance / time
Where
Distance = 150 mile
Time = 3 hours
Substitute the values into the formula
Speed = 150/3 = 50 mile/ hours
From Point B to Point A
Distance = 150 miles
Time = 5 hours
Where speed = distance/ time
substitute all the parameters into the formula
Speed = 150/5 = 30 mph
Therefore, The car travels at 50 mph for the first half and 30 mph for the second half.
The correct answer is option D
A fire cracker is fired and it rises to a height of 1000 m. Find the velocity by which it was
released and the time taken by it to reach the highest point (take a = 10 m/s²).
Answer:
Explanation:it is too easy
1. A physical quantity P is related to four observables a, b and c as follows: P= (a3b 2 /c4 ) The percentage errors of measurements in a, b and c are 1%, 4% and 2% respectively. What is the percentage error in quantity P?
Answer:
The percentage error in quantity P is 19%.
Explanation:
It is given that,
A physical quantity P is related to four observables a, b and c as follows:
[tex]P=\dfrac{a^3b^2}{c^4}[/tex]
The percentage errors of measurements in a, b and c are 1%, 4% and 2% respectively.
We need to find the percentage error in quantity P. It is given by :
[tex]\dfrac{\Delta P}{P}\times 100=(3\times \dfrac{\Delta a}{a}+2\times \dfrac{\Delta b}{b}+4\times \dfrac{\Delta c}{c})\\\\=3\times 1+2\times 4+4\times 2\\\\\dfrac{\Delta P}{P}\times 100=19\%[/tex]
So, the percentage error in quantity P is 19%.
A student measures the depth of a water well with an adjustable frequency audio oscillator. 2 successive resonant frequencies are heard at 40Hz and 50Hz. What is the depth of the well?
Answer:
17.15 m
Explanation:
Assuming the well is empty (full of air instead of water), the speed of sound is v = 343 m/s.
The water well acts as a pipe closed at one end. Therefore, the depth of the water well must be an odd multiple of a quarter of the resonant wavelength.
L = (2n − 1) λ/4, n = 1, 2, 3, etc.
v = λf, so λ = v/f. Substituting:
L = (2n − 1) v/(4f)
Solving for frequency:
f = (2n − 1) v/(4L)
The difference between two successive resonant frequencies is therefore:
Δf = (2(n+1) − 1) v/(4L) − (2n − 1) v/(4L)
Δf = (2n + 1) v/(4L) − (2n − 1) v/(4L)
Δf = 2 v/(4L)
Δf = v/(2L)
Plugging in values:
50 Hz − 40 Hz = 343 m/s / (2L)
2L = 34.3 m
L = 17.15 m
A physics student stands on a cliff overlooking a lake and decides to throw a softball to her friends in the water below. She throws the softball with a velocity of 23.5 m/s at an angle of 39.5∘ above the horizontal. When the softball leaves her hand, it is 11.5 m above the water. How far does the softball travel horizontally before it hits the water? Neglect any effects of air resistance when calculating the answer.
Answer:
66.86m
Explanation:
Velocity of ball thrown, u = 23.5 m/s
Initial height of the ball above the water, H = 11.5 m
Angle of projection, θ = 39.5°
Vertical components of veloclty = usinθ
Horizontal components of veloclty = ucosθ
The soft ball hits the water after time 't'
Considering the second equation of motion
S = ut + 1/2at^2........ 1
But since the ball went through motion under gravity ( free fall ) rather than linear motion, then equation 1 can be rewritten as:
H = ut +/- 1/2gt^2
H = - 11.5m
U = usinθ
θ = 39.5°
a = -g = -9.8m/s^2
- 11.5m = 23.5(sin39.5°)t + 1/2(-9.8)t^2
-11.5m = 23.5(0.6360)t - 4.9t^2
-11.5m = 14.946t - 4.9t^2
4.9t^2 -14.946t-11.5m = 0
Since the ball drifted horizontally
D = (Ucosθ)t
Where θ = 39.5°
U = 23.5m/s t=
Alternatively,
horizontal component of the velocity is 23.5 cos 39.5º = 18.1331 m/s
now how long does it take the ball to raise to a peak and fall to the water.
vertical component of velocity = 23.5 sin 39.5º = 14.947m/s
time to reach peak t = v/g = 11.947/9.8 = 1.5252 sec
peak reached above cliff top is
h = ½gt² = ½(9.8)(1.5252)²
= ½×22.797
= 11.3985m
now the ball has to fall 11.3985+ 11.5 = 22.8985m
time to fall from that height is
t = √(2h/g) = √(2• 22.8986/9.8) = 2.1617 sec
add up the two times to get time it is in the air, 2.1617 + 1.5252 = 3.6869
now haw far does the ball travel horizontally in that time
d = vt = 18.1331 ×3.6869= 66.856m
= 66.86m
The wavelength of a radio wave varies inversely as its frequency. A wave with a frequency of 1800 kilohertz has a length of 200 meters. What is the length of a wave with a frequency of 360 kilohertz?
Answer:
1000meters
Explanation:
Let the wavelength of the radio wave be W and it's frequency be f. If the wavelength of a radio wave varies inversely as its frequency, then W∝1/f
W = k/f where k is the constant of proportionality.
k = Wf
If a wave with a frequency of 1800 kilohertz has a length of 200 meters, then k = 1800×200
k = 360,000kHzm
To get the length of a wave with a frequency of 360 kilohertz, we will substitute the value of k and f = 360kHz into the initial formula i.e
W = k/f
W = 360,000/360
W = 1000meters
Hence the length of a wave with a frequency of 360 kilohertz is 1000meters
