The 4.00 kg block is attached to a vertical rod by means of two strings. When the system rotates about the axis of the rod, the strings are extended as shown in the (Figure 1) and the tension in the upper string is 76.0 N.
Find the number of revolutions per minute at which the lower cord just goes slack.
Answers
Answer:
Let theta be angle of upper string with rod.
This a 3-4-5 triangle where R is distance of block from rod. (.75 - 1 - 1.25)
Fc = m w^2 R where Fc the centripetal force and w the angular velocity
Fc = T sin theta = T * .75 / 1.25 = .6 T = 45.6 N
w^2 = 45.6 / (4 * .75)
w = 3.90 /sec
RPM = 3.90 / sec * 60 sec / min / (2 * pi) = 37.2 RPM (2 pi rad / rev)
The number of revolutions per minute at which the lower cord just goes slack is 45.36 RPM.
The given parameters;
mass of the block, m = 4 kgthe tension on the upper string, T₁ = 76 NThe following triangle can be formed from the given diagram;
|
| 1 m
|---------x--------(θ) 4.00 kg
The hypotenuse of this triangle = 1.25 m
The height of the triangle = 1 m
The base of the triangle is calculated as;
[tex]x^2 = 1.25^2 - 1^2\\\\x^2 = 0.5625\\\\x = \sqrt{0.5625} \\\\x = 0.75 \ m[/tex]
Resolving the vertical component of the force;
Tension at the upper = Tension at the lower string
[tex]T_1 sin(\theta) = T_2 sin(\theta) + mg\\\\76 \times \frac{1}{1.25} = T_2 \times \frac{1}{1.25} + (4\times 9.8)\\\\76 = T_2 + 39.2\\\\T_2 = 76 - 39.2\\\\T_2 = 36.8 \ N[/tex]
Resolving the horizontal component of the force;
[tex]T_1cos(\theta) + T_2cos(\theta) = F_c\\\\T_1cos(\theta) + T_2cos(\theta) = mr\omega^2 \\\\76\times \frac{0.75}{1.25} \ + \ 36.8\times \frac{0.75}{1.25}= 4\times 0.75\tmes (\frac{2\pi N}{60} )^2\\\\67.68 = 0.0329N^2\\\\N^2 = \frac{67.68}{0.0329} \\\\N^2 = 2057.14\\\\N = \sqrt{2057.14} \\\\N = 45.36 \ rpm[/tex]
Thus, the number of revolutions per minute at which the lower cord just goes slack is 45.36 RPM.
Learn more here: https://brainly.com/question/14973925
Related Questions
The gravitational force between two asteroids is 2.59 × 10 (exponent)-6 N. The centers of mass are 2000 meters away and their masses are equal. What is the mass of each asteroid?
Answers
Answer:
[tex]2.79 \times 10^5 \ \text{kg}[/tex]
Explanation:
Newton's Law of Universal Gravitation:
[tex]$F= G\frac{m_1 m_2}{r^2}[/tex] F = force of gravity (N)G = gravitational constant [tex](6.67 \times 10^-^1^1 \ N\frac{m^2}{kg^2})[/tex][tex]m_1[/tex] = mass of Object 1 (kg)[tex]m_2[/tex] = mass of Object 2 (kg)r = distance between the center of mass (m)Let's convert our given information to scientific notation:
[tex]2000 \ m \rightarrow 2.0 \times 10^3 \ m[/tex]Now using the gravitational force and the distance between centers of mass that are given, we can plug these into Newton's law:
[tex]2.59 \times 10^-^6 $\ N = 6.67 \times 10^-^1^1 \ N \frac{m^2}{kg^2} \times \frac{m_1 m_2}{(2.0 \times 10^3 \ m)^2}[/tex]Remove the units for better readability.
[tex]2.59 \times 10^-^6=6.67 \times 10^-^1^1 \frac{m_1m_2}{(2.0 \times 10^3)^2}[/tex]Divide both sides of the equation by the gravitational constant G.
[tex]\frac{2.59 \times 10^-^6}{6.67 \times 10^-^1^1} =\frac{m_1m_2}{(2.0 \times 10^3)^2}[/tex]Distribute the power of 2 inside the parentheses.
[tex]\frac{2.59 \times 10^-^6}{6.67 \times 10^-^1^1} =\frac{m_1m_2}{2.0 \times 10^6}[/tex]If we evaluate the left side of the equation, we get:
[tex]3.88305847 \times 10^4 = \frac{m_1m_2}{2.0 \times 10^6}[/tex]Multiply both sides of the equation by r.
[tex]7.76611694 \times 10^1^0= m_1m_2[/tex]In order to find the mass of one asteroid, we can use the fact that both asteroids have the same mass, therefore, we can rewrite [tex]m_1m_2[/tex] as [tex]m^2[/tex].
[tex]7.76611694 \times 10^1^0= m^2[/tex]Square root both sides of the equation.
[tex]m=\sqrt{7.76611694 \times 10^1^0}[/tex][tex]m=2.78677536 \times 10^5[/tex] [tex]m=2.79 \times 10^5[/tex]Since m is in units of kg, we can state that the mass of each asteroid is 2.79 * 10⁵ kg.
An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a less dense liquid. What would you observe?
Answers
Answer:
The fraction of its volume inside liquid is increased .
Explanation:
According to principle pf floatation , an object floats on the surface of water
when the weight of liquid displaced by it becomes equal to weight of the object . weight of the liquid depends upon the density of the liquid .
In the second case , when the body is dipped into liquid of lesser density , in order to balance the weight of body , more volume of liquid will be displaced so that weight of displaced liquid becomes equal to object's weight . So the body floats with greater depth inside liquid . The fraction of its volume inside liquid is increased .
An object has a kinetic energy Ek. What happens to the kinetic energy if we:
(a) double m?
(b) triple v?
Answers
K=
2
1
mv
2
When, v=2v,
K
′
=
2
1
m(2v)
2
K
′
=4×
2
1
mv
2
K
′
=4K
Hence, when velocity is doubled, kinetic energy becomes 4 times.
What is energy?
Question 1 options:
force × distance
force
chemical change
the ability to do work
Answers
Answer:
The ability to do work
Explanation:
Energy can be defined as the ability to do work. We apply energy in basically everything we do in life, energy is needed to walk or move from one position to another, it is required to eat and do other basic things of life. The body system converts the food that is being consumed into energy, this energy can be switched from one form to another.
There are various forms of energy which include solar energy , wind energy, electrical energy, mechanical energy, kinetic energy, potential energy etc. This forms of energy can be converted from one form to anothe but cannot be destroyed.
Answer:
ability to work
Explanation:
Create a hypothesis for this testable question: How does price affect the amount of chocolate people buy?
Answers
Answer:
IF the price of chocolate increases, THEN the amount of chocolate people buy decreases
Explanation:
In a scientific investigation, an observation is first made. Based on this observation, a scientific question is then asked. However, a HYPOTHESIS is given next to explain the question asked. A hyothesis is a testable explanation given to solve an observed problem or provide a possible answer to a question.
The hypothesis must be subject to testing via EXPERIMENTATION. A hypothesis usually goes in an IF, THEN format. In this case with the testable question: How does price affect the amount of chocolate people buy?
A hypothesis that can explain this question is: IF the price of chocolate increases, THEN the amount of chocolate people buy decreases.
A major artery with a 1.7 cm2 cross-sectional area branches into 18 smaller arteries, each with an average cross-sectional area of 0.4 cm2. By what factor is the average velocity of the blood reduced when it passes into these branches
Answers
Answer:
0.14
Explanation:
Flow rate is the volume flowing through a point at a particular time, in calcuing flow rate we have
Q= v*t
it in terms of Area, we have Q= A*v
Where A= area
v= velocity.
Solving the question , flow rate is constant then
A*v= constant
A(i) v(i)= A(f) v(f)
Where A(i)= initial area= 1.00cm^2
A(f)= final area= 0.400cm^2
V(i) and V(f) are the initial and final velocity respectively and the ratio of the two will gives us the factor
Substitute the values into the equation we have
1 V(i)= 4 V(f)
But we were told that the cross sectional area of 1.00cm^2 branches into 18 smaller arteries.
Then
1 V(i)=0.4 V(f)*(18)
1 V(i)=7.2V(f)
Then if we find the ratio of the velocity, we will get the factor.
V(f)/V(i)= 1/7.2
V(f)/V(i)=0.14
Hence, the factor of the average velocity of the blood reduced when it passes into these branches is 0.14
PLEASE HELP.
How does the motion of our solar system compare to the motion of the Milky Way?
Answers
The Solar System moves through the galaxy with about a 60° angle between the galactic plane and the planetary orbital plane. The Sun appears to move up-and-down and in-and-out with respect to the rest of the galaxy as it revolves around the Milky Way and
This speed is not unusual for the stars around us and is our “milling around” speed in our suburban part of the Galaxy. In addition to the individual motions of the stars within it, the entire Galaxy is in spinning motion like an enormous pinwheel.
Mechanical energy appears in the form of _____ energy and _____ energy.
Answers
Answer:
Potential and kinetic
Explanation:
If you are doing ck12 this is the answer
Select the correct term to complete each sentence. If you the wavelength, the electromagnetic radiation energy will double. The energy of the electromagnetic radiation will if you halve the wavenumber. When the frequency of the light is doubled, its energy will
Answers
Answer:
A) If you halve the wavelength, the electromagnetic radiation energy will double.
B) The energy of the electromagnetic radiation will halve if you halve the wavenumber.
C) When the frequency of the light is doubled, its energy will double.
Explanation:
The function for the light frequency is given as
The energy supplied to each electron is doubled by halving the wavelength, nearly doubling its kinetic energy by two after it is free from the metal. It is important to remember that for a given period of time, the number of electrons ejected will remain constant.
Cheers
HELPPP MEEE PLEADEEEE How could a cow have more momentum than a tiger ? Explain
Answers
Answer:
If a cow has a greater mass than the tiger, it has greater momentum, but only if they are moving at the same speed, or the tiger is going slower (i think)
Explanation:
the quantity of motion of a moving body, measured as a product of its mass and velocity.
If an 800.0 Kg sports car slows to 8.0 m/s in the forward direction to check out an accident scene and a 1200.0 kg pick-up truck behind them continues traveling at 15.0 m/s forward, with what velocity will the two move if they lock bumpers after a rear-end collision
Answers
Answer:
12.2m/sExplanation:
Step one:
given data
mass m1=800kg
velocity v1=8m/s
mass m2= 1200kg
velocity v2=15m/s
Note: the two bodies move with the same velocity after collision, hence the common velocity is v=?
Step two:
the expression for the total momentum is
m1v1+m2v2=v(m1+m2)
substituting we have
800*8+1200*15=v(800+1200)
6400+18000=v(2000)
24400=2000v
divide both sides by 2000 to find v
v=24400/2000
v=12.2m/s
Their common velocity is 12.2m/s
A 180-kg load is hung on a wire of length of 4.70 m, cross-sectional area 2.000 10-5 m2, and Young's modulus 8.00 1010 N/m2. What is its increase in length?
Answers
i saw it online once but i cant find it so i would look this up on maybe quizlet i use it a lot and it helps
A train of mass 3.3 × 10^6 kg is moving at a constant speed up a slope inclined at an angle of 0.64°
to the horizontal. The engine of the train is producing a useful output power of 14 MW.
Assume that there are no frictional forces opposing the motion of the train.
What is the speed of the train?
A 0.43 m s–1 B 4.2 m s–1 C 39 m s–1 D 380 m s–1.
Ans is C how?
ref: Q14 - 9702_s18_qp_11
Answers
Answer:
C. 39 m/s
Explanation:
First we need to calculate the total force required to move the train along the inclined plane. So, it is clear that the work done will be equal to the component of the weight that is parallel to the inclined plane, because there is no frictional force present:
Force = F = mg Sin θ
where,
m = mass of train = 3.3 x 10⁶ kg
g = 9.8 m/s²
θ = Angle of Inclination = 0.64°
Therefore,
F = (3.3 x 10⁶ kg)(9.8 m/s²)Sin 0.64°
F = 3.612 x 10⁵ N
Now, the formula for power is:
P = FV
V = P/F
where,
V = Velocity of Train = ?
P = Power of Engine = 14 MW = 1.4 x 10⁷ W
Therefore,
V = 1.4 x 10⁷ W/3.612 x 10⁵ N
V = 38.75 m/s
which is approximately equal to:
C. 39 m/s
The speed of train is 39 m/s. Hence, option (C) is correct.
Given data:
The mass of train is, [tex]m = 3.3 \times 10^{6} \;\rm kg[/tex].
The angle of inclination is, [tex]\theta = 0.64^ {\circ}[/tex].
The useful power output value is, [tex]P= 14 \;\rm MW = 14 \times 10^{6} \;\rm W[/tex].
The work done will be equal to the component of the weight that is parallel to the inclined plane, because there is no frictional force present. So, the total force required to move the train along the inclined plane is given as,
[tex]F = mg sin \theta\\\\F = 3.3 \times 10^{6} \times 9.8 \times sin0.64\\\\F = 361233.75 \;\rm N[/tex]
Now, use the formula of the power to obtain the value of speed as,
[tex]P = F \times v\\\\14 \times 10^{6} =361233.75 \times v\\\\v \approx 38.75 \;\rm m/s[/tex]
Thus, the speed of train is 39 m/s. Hence, option (C) is correct.
Learn more about the power output here:
https://brainly.com/question/22285866
You are an electrician working on a house. What type of circuit should you use for the house so that the owners don’t call to complain about their wiring? Why use this circuit?
Answers
Answer: Parallel
Explanation: Parallel because you don’t want all the lights to go out because of one light.
The electrical wiring and safety devices applied have to be perfect for non complainable circuit system in houses. One thing have to ensure that all the electrical components needs to follow the requirements set by national electrical code.
What are circuits?Circuits are way for the passage of electrical current which consists of electrical wires and devices such as bulbs, fan etc. The circuit system have to be properly designed so that no overload or short circuit can be occured.
Proper thermal insulations for cables and wires have to be chosen. Moreover, all the electrical components should follow the standard requirements set by local bodies or national electrical code.
Safety devices such as circuit breaker or switches like fuse of standard quality must be applied to protect the devices. Circuit breakers are more better than fuses because they don't need replacements.
Similarly, the selection of wires of cables have to careful and need to check the quality of plastic sheaths on them.
To find more on electrical circuits, refer here:
https://brainly.com/question/29032441
#SPJ5
The shortest wavelength of visible light is approximately 400 nm express the wavelength in centimeters
Answers
Answer:
4x [tex]10^{-5}[/tex] cm
Explanation:
400nm = 400 x [tex]10^{-9}[/tex] m
1m = 100 cm
400 x [tex]10^{-9}[/tex] m = 400 x [tex]10^{-9}[/tex] x 100 cm
ans : wavelength of light = 4x [tex]10^{-5}[/tex] cm
Answer:
[tex]4 * 10^{5}[/tex]
Explanation:
[tex]1c m = 1*10^-{7}nm[/tex]
what is an Electrical transformer?
Answers
Answer:
A transformer is a passive electrical device that transfers electrical energy from one electrical circuit to another, or multiple circuits.
Explanation:
Hope it helps
Answer:
A transformer with eletric abilities.
Explanation:
Which best describes the law of conservation of mass? The coefficients in front of the chemicals in the reactants should be based on the physical state of the products. Products in the form of gases are not considered a part of the total mass change from reactants to products. When reactants contain both a solid and a liquid, the solid counts toward the overall mass and the liquid does not. O The mass of the reactants and products is equal and is not dependent on the physical state of the substances.
Answers
Answer:
Explanation:
1. when both sides of the reactants and the products are equal
like h+oh ⇒ h20
hydrogen has 2 atoms on both sides and oxygen has one on both sides
2. no they are put to balance the equation
3. nope they are treated equally as all the other states
4. no if u are talking about a formula unit like NaCl for example it is aqueous not each element taken on its own if u are talking about just elements then i said before all states are treated equally
5. yup
A bug crawled 35 meters in 20 seconds. What was the bugs velocity ?
(EXPLAIN)
Answers
How fast does water flow from a hole at the bottom of a very wide, 7.1 mm deep storage tank filled with water
Answers
Answer:
The water will move fasterExplanation:
This happens as part of the consequences of the continuity of an incompressible fluid, of which water is an example.
so as the water emerges from the wider section the flow velocity increases and vice versa.
Hence the flow velocity in indirectly proportional to the area
The continuity equation is given below for our analysis
[tex]A1V1=A2V2\\[/tex]-------------------1
where
A1= the area of the wider section of the tank
V1= the flow velocity from the wider section
A2= the area of the hole at the bottom
V2= velocity of flow at the bottom.
What is the horizontal component of a ball thrown at a 27 degree angle at 16 m/s?
Answers
Answer:
14.25 m/s
Explanation:
In this problem, we need to find the horizontal component of a ball thrown at a 27 degree angle at 16 m/s.
It can be given by :
[tex]v_x=v\cos\theta\\\\=16\times \cos(27)\\\\=14.25\ m/s[/tex]
So, the horizontal component of the ball is 14.25 m/s.
A hunter is practicing hitting a target that is down range. If the arrow leaves the bow at a velocity of 30ms at an angle of 40° above the horizontal.
a.
Find out how far down range the arrow goes.
b. What is the maximum altitude the arrow reaches?
Answers
Answer:
Explanation:
range of projectile = u² sin2θ / g
u = 30 m /s
θ = 40°
range = 30² x sin 80 / 9.8
= 90.44 m
b )
maximum altitude H = u² sin²θ / 2 x g
= 30² sin²40 / 9.8
= 37.94 m .
Electromagnetic waves is what type of energy
Answers
Answer:
Energy waves that have both an electric and magnetic field.
Explanation:
what is the acceleration of a 5kg object pushed by 50 n
Answers
Answer:
i think it is 10m/s^2
force divide by mass
why it is important to take care of our body?
Answers
Answer:
You need to care for the body to stay fit, healthy and clean.
What is the period of revolution about the Sun for an asteroid with a semimajor axis of 3 AU in the middle of the asteroid belt?
Answers
Answer:
The period of revolution is 5.2 years.
Explanation:
The period of revolution about the Sun for an asteroid can be found using Kepler's third law:
[tex] p^{2} = a^{3} [/tex] (1)
Where:
p: is the period =?
a: is the semimajor axis (average distance from Sun) = 3 AU
By entering "a" value into equation (1) we have:
[tex] p = \sqrt{a^{3}} = \sqrt{(3)^{3}} = 5.2 y [/tex]
Therefore, the period of revolution about the Sun for an asteroid in the middle of the asteroid belt is 5.2 years.
I hope it helps you!
Which statement is supported by this scenario?
Yanni is sitting in the stands watching a football game.
The quarterback runs forward toward the end zone
and throws a pass straight downfield to a player for a
touchdown. The quarterback ran at a speed of 8 m/s
and threw the ball with a speed of 15 m/s.
For Yanni, the speed of the ball is 23 m/s, and for
the quarterback, the speed of the ball is 15 m/s.
For Yanni, the speed of the ball is 15 m/s, and for
the quarterback, the speed of the ball is 8 m/s.
For both Yanni and the quarterback, the speed of
the ball is 23 m/s.
For both Yanni and the quarterback, the speed of
the ball is 15 m/s.
Answers
Answer:
A
For Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Explanation:
Right on edge 2021
The statement supported by this scenario is, for Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Relative speed of the ballThe relative speed of the ball is determined with respect to frame of reference.
For Yanni at rest ( zero speed);Vr/b = va + vb
Vr/b = 8 + 15 = 23 m/s
For quarterback in motionVr/b = va + vb
Vr/b = 0 + 15 = 15 m/s
Thus, the statement supported by this scenario is, for Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Learn more about relative speed here: https://brainly.com/question/17228388
#SPJ2
A penny and a quarter are embedded in the concrete bottom of a swimming pool filled with water. Which of these coins experiences the greater downward force due to water pressure acting on it? Explain.
Answers
Answer: The quarter, because it has a larger surface area.
Explanation:
remember the equation:
Pressure = Force/Area
Now, if we isolate Force, we get:
Force = Pressure*Area.
The pressure will be the same for both coins, but the area is not.
Then the one with a larger surface area will suffer a greater downward force. (We can consider the area as the area of the top or bottom of the coin)
The area of a circle of diameter d, is:
A = pi*(d/2)^2
where pi = 3.14
The penny has a diameter of 19.05 mm, then its area is:
A = 3.14*(19.05mm/2)^2 = 284.87mm^2
The quarter has a diameter of 24.26mm, then the area is:
A = 3.14*(24.26mm/2)^2 = 462 mm^2
Then the quarter has a larger area, this means that the quarter will experience the greater downward force due to water pressure.
If each of the three rotor helicopter blades is 3.50 m long and has a mass of 120 kg , calculate the moment of inertia of the three rotor blades about the axis of rotation.
Answers
Answer:
1470kgm²
Explanation:
The formula for expressing the moment of inertial is expressed as;
I = 1/3mr²
m is the mass of the body
r is the radius
Since there are three rotor blades, the moment of inertia will be;
I = 3(1/3mr²)
I = mr²
Given
m = 120kg
r = 3.50m
Required
Moment of inertia
Substitute the given values and get I
I = 120(3.50)²
I = 120(12.25)
I = 1470kgm²
Hence the moment of inertial of the three rotor blades about the axis of rotation is 1470kgm²
A hydrogen atom in an excited state absorbs a photon of wavelength 411 nm. What were the initial and final states of the hydrogen atom?
Answers
Answer:
The initial and final states of the hydrogen atom were n=2 and n=6 respectively.
Explanation:
We must first obtain the energy of the photon;
E= hc/λ
where;
h= Plank's constant = 6.6 * 10^-34 JS
c= speed of light = 3* 10^8 m/s
λ = wavelength of light= 411 nm = 411* 10^-9 m
Substituting values;
E = 6.6 * 10^-34 * 3* 10^8 / 411* 10^-9
E = 4.8 * 10^-19 J or 3.0 eV
But ;
En = 13.6/n^2
So E = En final - En initial
3.0 = -13.6(1/n^2final - 1/n^2initial)
If we substitute n^2final = 6 and n^2 initial = 2 then the RHS becomes approximately equal to the LHS
Therefore the initial and final states of the hydrogen atom were n=2 and n=6 respectively.
Can anyone do this for me thanks
Answers
Answer:
Question 3: Shortest Wavelenght
Question 4: Longes Wavelenghth
Explanation: