từ độ cao h=2m một vật bắn lên với vận tốc ban đầu V0=10(m/s), hợp với phương ngang 1 góc 30 độ.Hãy xác minh
a. Thời gian chuyển động của vật ?
b. Độ lớn vận tốc tại điểm chạm đất
Answer:
A IS THE ANSWER
Explanation:
HOPE IT HELPS AND PLEASE MARK AS BRAINLIST
The elevation at the base of a ski hill is 350 m above sea level. A ski lift raises a skier (total mass=72 kg, including equipment) to the top of the hill. If the skier's gravitational potential energy relative to the base of the hill is now 9.2 x 105 J, what is the elevation at the top of the hill?
The elevation at the top of the hill is 1,653.85 m.
The given parameters;
initial height of the skier, h₁ = 350 mlet the final height of the skier at the hill top, = h₂total mass, m = 72 kggravitational potential energy of the skier, P.E = 9.2 x 10⁵ JThe elevation at the top of the hill is calculated as follows;
[tex]P.E = mg\Delta h\\\\P.E = mg(h_2 -h_1)\\\\h_2 -h_1 = \frac{P.E}{mg} \\\\h_2 = \frac{P.E}{mg} + h_1\\\\h_2 = \frac{9.2 \times 10^5 }{72 \times 9.8} \ + \ 350 \ m\\\\h_2 = 1,653.85 \ m[/tex]
Thus, the elevation at the top of the hill is 1,653.85 m.
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a convex mirror and a plane mirror both give virtual and erect images still a convex mirror is used in vehicles. why?
Pls answer thiss
Answer:Convex mirrors are used because these mirrors provide a wider viewing angle than a plane mirror. This wide angle will help you getting more information/overview than what is happening at a narrow spot right behind the car if you use a plane mirror.
With a convex mirror you are for example able to detect an overtake (by the car behind you) early, if you for some reason wanted to turn left into another lane at the same moment the overtake took place - so you then can prevent a collision. Convex mirrors are simply covering a much larger area behind the car than plane mirrors do. And in the US, on the mirrors there is a text explaining that the vehicle behind you is closer than it appears - some kind of an idiot explanation in case some driver took the mirror image literally….because in the mirror image of a convex mirror, everything looks smaller and further away than they actually are.
Explanation: mark me as brainliest this is my best answer till now
A golfer hits golf ball, imparting to it an initial speed of 53 m/s directed 27° above the horizontal. Assuming that the
mass of the ball is 41g and the club and the ball are in contact for 1.0 ms. Find
b) the direction of the average force exerted on the ball by the club:
Answer:
Explanation:
An impulse results in a change of momentum
FΔt = mΔv
F = mΔv/Δt
F = 0.041(53 - 0) / 0.001
F = 2,173 N 27° above horizontal
A flywheel, rotating about its axis at a rate of 4 rev/s is acted upon by a torque of 25 Nm for 10 sec. If the wheel has moment of inertia of 1.2 kgm^2, what would be the speed of the wheel at the end in rev/s?
The applied torque increases the angular speed by the application of an
angular acceleration.
The speed after 10 seconds is approximately 37.16 rev/s.Reasons:
The speed of the flywheel at the axis = 4 rev/s
The torque applied, T = 25 N·m
The time the torque is applied, t = 10 sec
Moment of inertia of the flywheel, I = 1.2 kg·m²
Required:
The speed at the end of the 10 seconds
Solution:
T = I·α
Where;
α = Angular acceleration
[tex]\displaystyle \alpha = \frac{T}{I}[/tex]
Therefore;
[tex]\displaystyle \alpha = \frac{24 \ N\cdot m}{1.2 \ kg \cdot m^2} = \mathbf{20\frac{5}{6} \ s^{-2}}[/tex]
The rotational speed, ω = ω₀ + α·t
Which gives;
[tex]\displaystyle \mathrm{The \ angular \ speed, } \ \omega = \frac{2 \cdot \pi \times 4 \ rad }{s} = \frac{8 \cdot \pi \ rad }{s}[/tex]
ω₀ = 8·π rad/s
Which gives;
[tex]\displaystyle \omega = \mathbf{8 \cdot \pi +2 \frac{5}{6} \times 10} = 233.47[/tex]
The speed of the wheel in revolution per second is therefore;
[tex]\displaystyle Speed \ in \ rev/s = \frac{8 \cdot \pi +2 \frac{5}{6} \times 10}{2\cdot \pi} \approx 37.16[/tex]
The speed after 10 seconds is approximately 37.16 rev/s.
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1- a car speeds up to get onto the freeway. it goes from 21 m/s to 39 m/s in 4.1 seconds. How far did it travel??
2- a boulder fell off a cliff and fell for 4.1 seconds. How tall was the cliff?
Answer:
Explanation:
1) average velocity is
v = (21 + 39)/2 = 30m m/s
d = vt 30(4.1) = 123 = 120 m
2) d = ½gt²
d = ½(9.8)(4.1²)
d = 82.369 = 82 m
when rounding to the two significant digits of the question numerals.
Goal statement write a positive statement that includes your desired outcome and your imagine preferred future after development
A goal statement may involve how to develop physical skills in a given outdoor activity (e.g., soccer) in order to reach my maximum potential. It involves a statement of purpose.
A goal statement is a statement of purpose that describes long-term professional and/or motivational objectives.
A goal statement involves writing a statement about how to reach personal objectives, i.e., how to accomplish a career, job title, sports skills, educational training, etc.
An excellent statement of purpose should ideally be clear, specific, acceptable, time-bound and realistic.
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If a battery causes a wire to carry a current of 4 Amps how many coulombs of charge flow past any point in the wire in 3 seconds
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
According to above question ~
Current (I) = 4 AmperesTime (t) = 3 seconds Charge (q) = ?Let's find the charge (q) by using formula ~
[tex]I = \dfrac{q}{t} [/tex][tex]4 = \dfrac{q}{3} [/tex][tex]q = 4 \times 3[/tex][tex]q = 12 \: \: coulombs[/tex]Hence, 12 coulombs of charge flow past any point in the wire in 3 seconds
if fire needs oxygen to burn, where does the sun get oxygen if there is no oxygen in space?
The sun is not a burning fire.
It's much much much hotter than that.
The sun's energy is the result of continuous nuclear fusion in it's core. We know how to do that on Earth, but the only thing we've been able to use it for so far is hydrogen bombs and other thermonuclear weapons.
what is the velocity of this graph between points a and b? 0.0m/s 2.5m/s 5.0m/s 6.0m/s?
Answer:
Pick c is the right one
Explanation:
5.0m/s
A domestic water heater holds 189 L of water at 608C, 1 atm. Determine the exergy of the hot water, in kJ. To what elevation, in m, would a 1000-kg mass have to be raised from zero elevation relative to the reference environment for its exergy to equal that of the hot water
A.
The energy of the hot water is 482630400 J
Using Q = mcΔT where Q = energy of hot water, m = mass of water = ρV where ρ = density of water = 1000 kg/m³ and V = volume of water = 189 L = 0.189 m³,
c = specific heat capacity of water = 4200 J/kg-°C and ΔT = temperature change of water = T₂ - T₁ where T₂ = final temperature of water = 608 °C. If we assume the water was initially at 0°C, T₁ = 0 °C. So, the temperature change ΔT = 608 °C - 0 °C = 608 °C
Substituting the values of the variables into the equation, we have
Q = mcΔT
Q = ρVcΔT
Q = 1000 kg/m³ × 0.189 m³ × 4200 J/kg-°C × 608 °C
Q = 482630400 J
So, the energy of the hot water is 482630400 J
B.
The elevation the mass would have to be raised from zero elevation relative to the reference environment for its exergy to equal that of the hot water is 49248 m.
Using the equation for gravitational potential energy ΔU = mgΔh where m = mass of object = 1000 kg, g = acceleration due to gravity = 9.8 m/s² and Δh = h - h' where h = required elevation and h' = zero level elevation = 0 m
Since the energy of the mass equal the energy of the hot water, ΔU = 482630400 J
So, ΔU = mgΔh
ΔU = mg(h - h')
making h subject of the formula, we have
h = h' + ΔU/mg
Substituting the values of the variables into the equation, we have
h = h' + ΔU/mg
h = 0 m + 482630400 J/(1000 kg × 9.8 m/s²)
h = 0 m + 482630400 J/(9800 kgm/s²)
h = 0 m + 49248 m
h = 49248 m
So, the elevation the mass would have to be raised from zero elevation relative to the reference environment for its exergy to equal that of the hot water is 49248 m.
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n which case will a beat frequency most likely occur?(1 point) two different instruments playing notes at the same frequency two different instruments playing notes at the same frequency two of the same instrument playing notes at the same frequency two of the same instrument playing notes at the same frequency two of the same instrument playing notes at slightly different frequencies two of the same instrument playing notes at slightly different frequencies two different instruments playing notes at very different frequencies
Answer:
two of the same instrument playing notes at slightly different frequencies
Explanation:
The correct answer is two of the same instrument playing notes at slightly different frequencies.
What is the frequency?Frequency is the number of occurrences of a periodic event per unit of time. In the context of sound waves, frequency refers to the number of complete cycles of a sound wave that occur in one second and is measured in units of Hertz (Hz).
In this question,
A beat frequency occurs when two sound waves with slightly different frequencies interfere with each other, resulting in a periodic variation in the amplitude of the resulting wave. The beat frequency is equal to the difference in frequency between the two original sound waves.
When two of the same instrument play notes at slightly different frequencies, the sound waves produced by each instrument will have slightly different frequencies due to differences in tuning or other factors. When the two sound waves interfere with each other, they will produce a beat frequency equal to the difference between their frequencies. This beat frequency will be audible as a periodic variation in the loudness or intensity of the sound.
In the other statements, There will not be any beat frequency because the sound waves being produced have either the same frequency or very different frequencies, which do not interfere with each other in a way that produces beats.
Therefore, The statement two of the same instrument playing notes at slightly different frequencies is correct.
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The elevation at the base of a ski hill is 350 m above sea level. A ski lift raises a skier (total mass=72 kg, including equipment) to the top of the hill. If the skier's gravitational potential energy relative to the base of the hill is now 9.2 x 105 J, what is the elevation at the top of the hill?
The elevation at the top of the hill is 1,653.85 m.
The given parameters;
initial height of the skier, h₁ = 350 mlet the final height of the skier at the hill top, = h₂total mass, m = 72 kggravitational potential energy of the skier, P.E = 9.2 x 10⁵ JThe elevation at the top of the hill is calculated as follows;
[tex]P.E = mg\Delta h\\\\P.E = mg(h_2 -h_1)\\\\h_2 -h_1 = \frac{P.E}{mg} \\\\h_2 = \frac{P.E}{mg} + h_1\\\\h_2 = \frac{9.2 \times 10^5 }{72 \times 9.8} \ + \ 350 \ m\\\\h_2 = 1,653.85 \ m[/tex]
Thus, the elevation at the top of the hill is 1,653.85 m.
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help me in the Infer one
Answer:
Overcurrents
Circuit breakers ("fuses" back in the day) are supposed to trigger when you are requesting past it more power (thus more current, since the tension is fixed and power is the product of voltsge times current). So whoever made that part of the grid did not foresee that many appliances.
Another option could be a short circuit somehwere but I think it is unlikely since the breaker would not trigger only when all three loads are powered on.
The photo shows a skateboarder pushing her foot against the ground as she rides down a hill.
How does this action cause the skateboarder’s speed to change?
Answer:
A
Explanation:
Down the hill, the net force increases if she pushes more forward.
Answer:
its a im just did the test
Explanation:
This is for Lipor only.
Answer:
im here\
Explanation:
What is the difference between the contagion theory and the convergence
theory?
O A. One deals with how people behave before a riot, and the other
deals with how people behave after a riot.
O B. One deals with adults with no power, and the other deals with
authority figures.
O C. One deals with how people are affected by a crowd, and the other
deals with how people actively drive a crowd's Behavior.
O D. One deals with people from democratic governments, and the
other deals with people from authoritarian governments.
Answer: Contagion theory states that crowds cause people to act in a certain way; convergence theory says the opposite, claiming that people who wish to act in a certain way come together to form crowds.
Explanation: Its C
A ball is thrown up onto a roof, landing 4 sec later at height of 20m above the release level. The balls path just before landing is angled at 60 degree with the roof.
a) find the horizontal distance d it travels.
b) what is the magnitude of the balls initial velocity?
c) what is the angle (relative to the horizontal) of the balls initial velocity?
Answer: 20
Explanation:
Which performs a function that is most like the function of a retina?
Answer:
The answer is ciliary body and focus the pupil. In addition, the ciliary body is a portion of the eye that contains the ciliary muscle that reins the shape of the lens and the ciliary epithelium that yields the aqueous humor. The ciliary body is a share of the uvea which is the layer of tissue that transports oxygen and nutrients to the eye nerves while the pupil is a hole positioned in the midpoint of the iris of the eye that permits light to foray the retina. It looks black since light rays incoming the pupil are moreover engrossed by the tissues in the eye openly or engrossed after diffuse reflections in the eye that typically miss leaving the fine pupil
Explanation:
Answer:the eye has many parts that must work together in order to produce clear vision
Explanation: correct on my test
6) The modern atomic model is called the _____.
A) central atom model
B) plum pudding model
C) nuclear atomic model
D) electron growth model
The modern atomic model is called the nuclear atomic model.
Therefore the correct answer is option C.
What are atomic models?There are many types of atomic models proposed in past based on their individual assumptions and the experimentations
John Dalton's atomic model.
The Plum Pudding Model, developed by J.J. Thomson,
Rutherford's model provided an explanation for the presence of a nucleus inside the atom.
In accordance with the current atomic model, atoms have a nucleus made up of protons and neutrons and an ethereal gradient or cloud surrounding them that houses electrons;
The modern atomic model is called the nuclear atomic model.
Thus, the correct answer is option C.
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2. Which of the following contributions did Louie De Broglie do for electronic structure of matter? A. determined the speed of electron of hydrogen atom B. proposed a theory that electrons showed characteristics similar to light C. provided mathematical operation for the characteristics of light D. recorded the movement of proton in the nucleus of an atom
❤️
Answer:
In 1924 Louis de Broglie introduced the idea that particles, such as electrons, could be described not only as particles but also as waves. This was substantiated by the way streams of electrons were reflected against crystals and spread through thin metal foils.
Explanation:
I know I probably didn't answer your question, I just used all of my knowledge that I learned about Louie De Broglie. Hope it helps!
Determine the unbalanced force necessary to accelerate a 2.60 kg object at a rate of 14.0 m/s².
Answer:
Explanation:
F = ma
F = 2.60(14.0)
F = 36.4 N
Objects 1 and 2 attract each other with a gravitational force of 45 units. If the mass of Object 1 is doubled, then the new gravitational fore will be ______ units.
Explanation:
Fgravity = G*(mass1*mass2)/D²
so, if you double one of the masses, what does that do to our equation ?
Fgravitynew = G*(2*mass1*mass2)/D²
due to the commutative property of multiplication
Fgravitynew = 2* G*(mass1*mass2)/D² = 2* Fgravity
so, the correct answer will be 2×45 = 90 units.
what two things make up an ionic bond?
For an object spinning around a central point, what will happen if its distance from the center is decreased?
A. Nothing will change.
B. Its acceleration will decrease.
C. Its acceleration will increase.
D. The centripetal force will decrease.
Answer:
Its acceleration will increase.
Explanation:
For an object spinning around a central point, Its acceleration will increase if its distance from the centre is decreased.
What is acceleration?The rate at which an item changes its velocity is known as acceleration, a vector quantity. If an object's velocity is changing, it is acceleration. The net acceleration that objects get as a result of the combined action of gravity and centrifugal force is known as the Earth's gravity
This is the acceleration of an object in a circle of radius r at a speed v. So, centripetal acceleration is greater at high speeds and in sharp curves smaller radii and for lager radii acceleration will be less.
acceleration, a = v²/r
For an object spinning around a central point, Its acceleration will increase if its distance from the centre is decreased.
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How many states of matter are there?
Answer:
3
Explanation:
state of matter are solid
liquid and
gases
A rocket ship has several engines and thrusters. While the Solid Rocket Booster (SRB) and main engines only work together during the first 2 minutes of flight, the main engines operate for a total of 8.5 minutes after the launch. Once the SRBs are released, the main engines alone accelerate the rocket from about 1341 m/s to 7600 m/s.
What is the acceleration of the SRB and main engine during the first 2.0 minutes of flight?
A. 52 m/s2
B. 13 m/s2
C. 9.8 m/s2
D. 11 m/s2
The acceleration of the SRB and main engine during the first 2.0 minutes of flight is 52.16 m/s².
The given parameters;
initial velocity of the engine, u = 1341 m/sfinal velocity of the engine, v = 7600 m/stime of motion, t = 2 minutes = 2 x 60 s = 120 sThe acceleration of the SRB and main engine is calculated as follows;
[tex]a = \frac{\Delta v}{\Delta t } \\\\a = \frac{7600 - 1341}{2 \times 60 s} \\\\a = 52.16 \ m/s^2[/tex]
Thus, the acceleration of the SRB and main engine during the first 2.0 minutes of flight is 52.16 m/s².
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numerical problems:
a.) convert 300K into the celsius scale.
b.) convert 220 centigrade scale into kelvin scale.
c.) convert 20 ventigrade scale into Fahrenheit scale.
d.) convert 260 Fahrenheit into centigrade. pls help me to solve this problems
A 64 kg student is standing atop a spring in an
elevator that is accelerating upward at 3.0 m/s2
The spring constant is 3000 N/m.
A) by how much is the spring compressed?
Answer:
192
Explanation:
A crane is lifting a 500 lb car. If the power of the crane 1.82 hp, find the velocity of the car.
Answer:
Explanation:
550 ft•lb/s / hp•(1.82 hp) / 500 lb = 2.00 ft/s