Answer:
1.884 meters per second
Explanation:
s = d/t
d = C = 2πr = 2π(6) = 37.68 m
t = 20 s
s = (37.68 m)/(20 s)
s = 1.884 m/s
The speed of the boy is 1.88 m/s while he is moving around a circular park of radius 6m and taking time 20 seconds.
What is speed?Speed can be defined as a measurement of how quickly the distance an object traveled changes with time. Speed is a scalar quantity as it has magnitude but no direction as a unit of measurement.
An object that moves quickly and with high speed, traveling a lot of ground in a lesser time.
Given, the radius of the circular park, r = 6m,
The time taken to cover one round of the park, t = 20 s
The total distance traveled by the boy is equal to the circumference of the circular park, so
Circumference of park, C = d = 2πr = 2× 3.14 × 6 =37.68 m
The speed of the boy, S = d/t
S = 37.68 /20
S = 1.88 m/s
Therefore, the speed of the boy is equal to 1.88 m/s.
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Sophie applies a 50 n force to push a box 2 meter across the floor calculate the smount of work done in the box
PLEASE HELP ASP WILL GIVE 50 POINT AND BRAINLIEST!!!!!!!!!!!!!
A. In the Bohr model of the hydrogen atom, the speed of the electron is approximately
2.16 × 10⁶ m/s. Find the central force acting on the electron as it revolves in a circular orbit of radius 5.17 × 10⁻¹¹ m.
Answer in units of N.
B. Find the centripetal acceleration of the electron
Explanation:
A. The centripetal force experienced by an electron as it goes around a hydrogen nucleus is given by
[tex]F_c = m_e\dfrac{v^2}{r}[/tex]
where [tex]m_e = \text{electron\:mass} = 9.11×10^{-31}\:\text{kg}[/tex]
[tex]r = 5.17×10^{-11}\:\text{m}[/tex] = orbital radius
[tex]v = 2.16×10^6\;\text{m/s}[/tex] = orbital velocity
so the centripetal force is
[tex]F_c = (9.11×10^{-31}\:\text{kg})\dfrac{(2.16×10^6\;\text{m/s})^2}{5.17×10^{-11}\:\text{m}}[/tex]
[tex]\;\;\;=8.22×10^{-8}\:\text{N}[/tex]
B. The electron's centripetal acceleration is given by
[tex]a_c = \dfrac{v^2}{r}[/tex]
Using the values from (A), we get
[tex]a_c = \dfrac{(2.16×10^6\;\text{m/s})^2}{5.17×10^{-11}\:\text{m}}[/tex]
[tex]\;\;\;=9.02×10^{22}\:\text{m/s}^2[/tex]
What is the half-life of the imaginary element Lokium? Show your work
Answer:What is the half life of the element Lokium?
The half-live of the element Lokium is 4.
Explanation:
sorry if im wrong, have good day
Answer:
The half-life of the element Lokium is 4
What is half-life?
Whether or not a given isotope is radioactive is a characteristic of that particular isotope. Some isotopes are stable indefinitely, while others are radioactive and decay through a characteristic form of emission. As time passes, less and less of the radioactive isotope will be present, and the level of radioactivity decreases. An interesting and useful aspect of radioactive decay is the half-life. The half-life of a radioactive isotope is the amount of time it takes for one half of the radioactive isotope to decay. The half-life of a specific radioactive isotope is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.
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a uniform thin rod of length l and mass m is allowed to rotate on a frictionless pin passing through one end. The rod is released from rest in the horizontal position. a.) What is the speed of the center of gravity when the rod reaches its lowest position? b.) What is the tangential speed of the lowest point of the rod when the rod reaches its lowest position?
Answer:
Explanation:
Potential energy gets converted to rotational kinetic energy
a) ½Iω² = mgh
½(mL²/3)ω² = mgL/2
(L/3)ω² = g
ω = [tex]\sqrt{3g/L}[/tex]
v(CG) = (L/2) [tex]\sqrt{3g/L}[/tex]
Not sure if you wanted angular speed or tangential speed of the CG so I gave both.
b) v = Rω = L [tex]\sqrt{3g/L}[/tex]
PLEASE ANSWER QUICK GIVING BRAINLIEST TO THE ONE WHO ANSWERS
Describe what happens when iron and oxygen combine. Can the change be reversed?
Answer:
iron combines with oxygen to produce rust, which is the compound named iron oxide.
Explanation:
True or False. Abraham and Sarah were in agreement regarding God's command to sacrifice Isaac.
Answer:
Explanation:
Not in Genesis. The proposed sacrifice of Isaac was all Abraham's doing. Sarah was not present and could not, therefore offer any input. It might have been covered in other Jewish writings, but it is not recorded in Genesis.
Since the book most widely used by Everyone is the Bible, I would answer false.
A 2.2 kg model rocket is shot straight up in the air from the ground, with an initial velocity of 36.4 m/s. The rocket reaches its maximum height, and falls back to the ground. What is the maximum height of the rocket? Round your answer to 2 decimal places.
Answer:
Explanation:
Ignoring friction, the initial kinetic energy will convert to maximum potential energy at its highest point.
PE = KE
mgh = ½mv²
h = v²/2g
h = 36.4²/ (2(9.81))
h = 67.53109...
h = 67.53 m
Suppose a bulldozer is being hauled at 50 km/h to a construction site on the back of a flatbed truck. From which reference point would the bulldozer not appear to be moving?
Answer:
from someone watching the bulldozer from the cab of the truck or from elsewhere on the flatbed.
Explanation:
Use the equation of motion to answer the question. Use the equation of motion to answer the question.
x=x0+v0t+12at2
An object has a starting position of x = 2 m, a starting velocity of 4.5 m/s, and no acceleration. Which option shows the final position of the object after 2 s?
The final position of the object after 2 s is 11 m.
Motion: This can be defined as the change in position of a body.
⇒ Formula:
x = x₀+v₀t+1/2(at²)........................ Equation 1⇒ Where:
x = Final position of the objectx₀ = Starting positionv₀ = Starting velocityt = timea = accelerationFrom the question,
⇒ Given:
x₀ = 4.5 m/st = 2 sx₀ = 2ma = 0 m/s²⇒ Substitute these values into equation 1
x = 2+(4.5×2)+1/2(0²×2)x = 2+9+0x = 11 mHence, The final position of the object after 2 s is 11 m
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Which statement is true for a series circuit
Answer: they have one path to flow
Explanation: share the same current
a 2000kg car initially traveling at a speed of 15 m/s is accelerated by a constant force of 10000 n for 3 seconds. the new speed of the car is
Answer:
The new speed of the car is 30 m/s.
Hope you could get an idea from here.
Doubt clarification - use comment section.
Can someone help me solve this problems please? It's a physics problem.
Answer:
i cant see
Explanation:
but im smart
As a result of friction, the angular speed of a wheel changes with time according to dθ/dt = ω0e^−σt where ω0 and σ are constants. The angular speed changes from 3.70 rad/s at t = 0 to 2.00 rad/s at t = 8.60 s.
a. Use this information to determine σ and ω0.
σ = _______s−1
ωo = ______rad/s
b. Determine the magnitude of the angular acceleration at t = 3.00 s.
______rad/s2
c. Determine the number of revolutions the wheel makes in the first 2.50 s
_______rev
d. Determine the number of revolutions it makes before coming to rest.
_______rev
Hi there!
a.
We can use the initial conditions to solve for w₀.
It is given that:
[tex]\frac{d\theta}{dt} = w_0e^{-\sigma t}[/tex]
We are given that at t = 0, ω = 3.7 rad/sec. We can plug this into the equation:
[tex]\omega(0)= \omega_0e^{-\sigma (0)}\\\\3.7 = \omega_0 (1)\\\\\omega_0 = \boxed{3.7 rad/sec}[/tex]
Now, we can solve for sigma using the other given condition:
[tex]2 = 3.7e^{-\sigma (8.6)}\\\\.541 = e^{-\sigma (8.6)}\\\\ln(.541) = -\sigma (8.6)\\\\\sigma = \frac{ln(.541)}{-8.6} = \boxed{0.0714s^{-1}}[/tex]
b.
The angular acceleration is the DERIVATIVE of the angular velocity function, so:
[tex]\alpha(t) = \frac{d\omega}{dt} = -\sigma\omega_0e^{-\sigma t}\\\\\alpha(t) = -(0.0714)(3.7)e^{-(0.0714) (3)}\\\\\alpha(t) = \boxed{-0.213 rad\sec^2}[/tex]
c.
The angular displacement is the INTEGRAL of the angular velocity function.
[tex]\theta (t) = \int\limits^{t_2}_{t_1} {\omega(t)} \, dt\\\\\theta(t) = \int\limits^{2.5}_{0} {\omega_0e^{-\sigma t}dt\\\\[/tex]
[tex]\theta(t) = -\frac{\omega_0}{\sigma}e^{-\sigma t}\left \| {{t_2=2.5} \atop {t_1=0}} \right.[/tex]
[tex]\theta = -\frac{3.7}{0.0714}e^{-0.0714 t}\left \| {{t_2=2.5} \atop {t_1=0}} \right. \\\\\theta= -\frac{3.7}{0.0714}e^{-0.0714 (2.5)} + \frac{3.7}{0.0714}e^{-0.0714 (0)}[/tex]
[tex]\theta = 8.471 rad[/tex]
Convert this to rev:
[tex]8.471 rad * \frac{1 rev}{2\pi rad} = \boxed{1.348 rev}[/tex]
d.
We can begin by solving for the time necessary for the angular speed to reach 0 rad/sec.
[tex]0 = 3.7e^{-0.0714t}\\\\t = \infty[/tex]
Evaluate the improper integral:
[tex]\theta = \int\limits^{\infty}_{0} {\omega_0e^{-\sigma t}dt\\\\[/tex]
[tex]\lim_{a \to \infty} \theta = -\frac{\omega_0}{\sigma}e^{-\sigma t}\left \| {{t_2=a} \atop {t_1=0}} \right.[/tex]
[tex]\lim_{a \to \infty} \theta = -\frac{3.7}{0.0714}e^{-0.0714a} + \frac{3.7}{0.0714}e^{-0.0714(0)}\\\\ \lim_{a \to \infty} \theta = \frac{3.7}{0.0714}(1) = 51.82 rad[/tex]
Convert to rev:
[tex]51.82 rad * \frac{1rev}{2\pi rad} = \boxed{8.25 rev}[/tex]
Find the magnitude of the potential difference between two points located 1.2 m apart in a uniform 700 N/C electric field, if a line between the points is parallel to the field. Express your answer in volts.
The magnitude of the potential difference between the two points is 840 V
To solve the problem above, we need to use the formula of Potential difference as related to distance and electric field.
Potential difference: This can be defined as the work required to move a unit charge from a point to another in an electric field.
⇒ Formula:
V = E×d.................. Equation 1⇒ Where:
V = Potential differenceE = Electric Fieldd = DistanceFrom the question,
⇒ Given:
E = 700 N/Cd = 1.2 m⇒ Substitute these values into equation 1
V = 700(1.2)V = 840 VHence, The magnitude of the potential difference between the two points is 840 V
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What can happen when untreated sewage water contaminates water?
Answer:
Health Effects ↯Life-threatening human pathogens carried by sewage include cholera, typhoid and dysentery. Other diseases resulting from sewage contamination of water include schistosomiasis, hepatitis A, intestinal nematode infections, and numerous others.
Explanation:
BRAINLIEST PLEASE • •︴︴
____
Raghu studies in grade 6th. He wants a cricket bat to be made by a carpenter. He tells the
that the length of the bat should be 7 hand spans. The tall carpenter tells Raghu that it
will be ready by tomorrow. When Raghu went to collect the bat the next day, he was very
disappointed. Why? Was the bat longer or shorter than what Raghu expected? Give reason.
carpenter
Based on the information given, it can be noted that the bat was either shorter or longer than what he expected.
From the information given, it was stated that Raghu wants a cricket bat to be made by a carpenter and he tells the carpenter that the length of the bat should be 7 hand spans.
Since he got disappointed when he collected the bat, the reason for this will be because the bat was either shorter or longer than what he requested.
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if a current of 2.0 A is flowing from point a to point b, the potential difference between Vb- Va (in V) is:
a. 6
b. 8
c. -6
d. -8
e. 22
Answer:
[tex]\huge\color{skyblue}\boxed{\colorbox{black}{Answer ☘}}[/tex]
[tex]total \: resistance \: ( R_{t} ) = (3 + 1)ohm \\ (since \: the \: resistors \: are \: connected \\ in \: series)[/tex]
[tex]current \: flowing \: through \: circuit(I) = 2A \\ \\ now... \: by \: ohms \: law \\ V = IR\\ V = (2)(4) \\ = > 8v[/tex]
therefore , option (b) is correct!!hope helpful~
Convert the decimal number 61078 to binary by using sum-of-weights method
Answer:
1110111010010110
Explanation:
I am not able to upload the working out using the sum of weights method sorry
Hey guys can you help me with this problem it's giving me a headache. "If 2500 kg roller coaster car begins its descent from 500m above above the first hill. What is its kinetic energy at the bottom of the hill."
The kinetic energy of the roller coaster at the bottom of the hill is 12250000 J
To answer this question, we must understand that the energy of a system is always conserved as explained by the law of conservation of energy.
The kinetic energy of the roller coaster will be equivalent to the potential energy of the roller coaster.
The kinetic energy of the roller coaster can be obtained as follow:
Mass (m) = 2500 KgHeight (h) = 500 mAcceleration due to gravity (g) = 9.8 m/s²Kinetic energy (KE) =?Kinetic energy = Potential energy
KE = mgh
KE = 2500 × 9.8 × 500
KE = 12250000 J
Therefore, the kinetic energy of the roller coaster is 12250000 J
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Make a generalization about Earth's magnetic field and its properties. In not more than 10 sentences.
Answer:
Earth's magnetic field (and the surface magnetic field) is approximately a magnetic dipole, with the magnetic field S pole near the Earth's geographic north pole (see Magnetic North Pole) and the other magnetic field N pole near the Earth's geographic south pole (see Magnetic South Pole). This makes the compass usable for navigation. The cause of the field can be explained by dynamo theory. A magnetic field extends infinitely, though it weakens with distance from its source. The Earth's magnetic field, also called the geomagnetic field, which effectively extends several tens of thousands of kilometres into space, forms the Earth's magnetosphere. A paleomagnetic study of Australian red dacite and pillow basalt has estimated the magnetic field to be at least 3.5 billion years old
You hang a light in front of your house using an
elaborate system to keep the 12-kg object in static
equilibrium (Figure 1). What are the magnitudes of the
forces that the ropes must exert on the knot connecting
the three ropes if 02 = 639 and 03 = 45° ?
The magnitudes of the forces that the ropes must exert on the knot connecting are :
F₁ = 118 N F₂ = 89.21 N F₃ = 57.28 NGiven data :
Mass ( M ) = 12 kg
∅₂ = 63°
∅₃ = 45°
Determine the magnitudes of the forces exerted by the ropes on the connecting knota) Force exerted by the first rope = weight of rope
∴ F₁ = mg
= 12 * 9.81 ≈ 118 kg
b) Force exerted by the second rope
applying equilibrium condition of force in the vertical direction
F₂ sin∅₂ + F₃ sin∅₃ - mg = 0 ---- ( 1 )
where: F₃ = ( F₂ cos∅₂ / cos∅₃ ) --- ( 2 ) applying equilibrium condition of force in the horizontal direction
Back to equation ( 1 )
F₂ = [ ( mg / cos∅₂ ) / tan∅₂ + tan∅₃ ]
= [ ( 118 / cos 63° ) / ( tan 63° + tan 45° ) ]
= 89.21 N
C ) Force exerted by the third rope
Applying equation ( 2 )
F₃ = ( F₂ cos∅₂ / cos∅₃ )
= ( 89.21 * cos 63 / cos 45 )
= 57.28 N
Hence we can conclude that The magnitudes of the forces that the ropes must exert on the knot connecting are :
F₁ = 118 N, F₂ = 89.21 N, F₃ = 57.28 N
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Hello I am absolutely stumped on these six physics problems. Please help me on them.
Answer:
Explanation:
20° from the normal = 110° from parallel
1a) τ = (200sin90)[6] + (75sin110)[3] - (100sin110)[3]
τ = 1,129.52305... = 1100 N•m CCW
1b) τ = 200(6)(sin90) + 75(-3)(sin(360-110)) + 100(3)(sin(270 + 20)
τ = 1,129.52305... = 1100 N•m CCW
1c) My directions agree, both are positive z by right hand rule.
1d) Moment of inertia for a thin rod about an axis perpendicular to its center is
I = (1/12)mL²
τ = Iα
α = τ/I = 1129.523 / ((1/12)(200)(12²)) = 0.4706 rad/s²
θ = ½αt²
θ = ½(0.4706)(2•60)² = 3,388.56916... radians
θ = 3400 radians
at which time is is spinning about 9 revolutions per second
Which of the following is NOT a function of the lens in the eye?
It can perform minor adjustments for distance.
It flattens when light rays from distant objects are to be focused.
It is a light receptor that generates nerve signals that are sent to the brain.
It maintains its spherical shape to view nearby objects.
Answer:
it is a light receptor that generates nerve signals that are sent to the brain
Explanation:
the lens are like the glasses, this means that is used to see things better. You just put them in your eye and that's all it's not connected to the brain
Answer:
c
Explanation:
9. P waves move faster than S waves A. True B. False
When Elements neutral atom contains 5 neutrons 4 electrons and 4 protons
Answer:
What is the atomic number of an atom that has 5 neutrons and 4 electrons? A neutral atom will have the same number of electrons is does protons. Since it has 4 protons, it must have an atomic number of 4. (That makes it beryllium.)
Explanation:
mark me brainliest please and thank you Ma'aM/Sir
Answer:
4 protons, 5 neutrons, and 4 electrons are there in an atom of beryllium.
How large is the tension in a rope that is being used to accelerate a 100 kg box upward at 2m/s2?
[tex]\\ \sf\Rrightarrow T=F[/tex]
[tex]\\ \sf\Rrightarrow T=ma[/tex]
[tex]\\ \sf\Rrightarrow T=100(2)[/tex]
[tex]\\ \sf\Rrightarrow T=200N[/tex]
Hey guys can you help me solve this problem "how long will it take a car travelling 30m/s to come to stop ifs its acceleration is -3 m/s2".
Answer:
10 seconds.
Explanation:
We can use a kinematic equation where we know the final velocity, initial velocity, acceleration, and need to determine the time t:
[tex]\displaystyle v_f = v_i + at[/tex]
The initial velocit is 30 m/s, the final velocity is 0 m/s (as we stopped), and the acceleration is -3 m/s².
Substitute and solve for t:
[tex]\displaystyle \begin{aligned} (0\text{ m/s}) & = (30 \text{ m/s}) + (-3 \text{ m/s$^2$}) t \\ \\ t & = \frac{-30\text{ m/s}}{-3 \text{ m/s$^2$}} \\ \\ & = 10 \text{ s} \end{aligned}[/tex]
Hence, it will take the car 10 seconds to come to a stop.
a car moving at 5 m/s accelerates at a rate of 10 m/s2 for 25 seconds. How far does it move during this time?
Answer:
t is time in s For example, a car accelerates in 5 s from 25 m/s to 3 5m/s. Its velocity changes by 35 - 25 = 10 m/s. Therefore its acceleration is 10 ÷ 5 = 2 m/s2
Explanation:
Where do hyperbolic comets originate?
A. the Oort cloud
B. the asteroid belt
C. the Kuiper belt
D. interstellar space
Answer:A.the Oort cloud
Explanation:
Answer:
try answer A..the Ootor cloud
A wire that is 1.0 m long with a mass of 90 g is under a tension of 710 N. When a transverse wave travels on the wire, its wavelength is 0.10 m. What is the frequency of this wave?
Answer:
890 HzI hope you liked my answer. Thank You!