Answer:
The acceleration is [tex]a = 2.5 \ m/s^2[/tex]
Explanation:
From the question we are told that
The mass of the metal block is [tex]m_b = 2 \ kg[/tex]
The mass flow rate of the water is [tex]\r m = 1\ kg/s[/tex]
The speed of the water of the water release is [tex]v_w = 5 m/s[/tex]
Generally according to the law of conservation of linear momentum
[tex]p_i = p_f[/tex]
Now [tex]p_i[/tex] is the initial momentum of the system which mathematically represented as
[tex]p_i = m_w * v_w + m_b * v_b[/tex]
Now [tex]m_w[/tex] is the mass of water at the point of contact with the block which can be deduced as [tex]m_w = 1 \ kg[/tex]
Now since at initial the block is at rest
[tex]v_b = 0 \ m/s[/tex]
So
[tex]p_i = 1 * 5[/tex]
[tex]p_i = 5 \ kgm/ s[/tex]
And [tex]p_f[/tex] is the final momentum of the system which mathematically represented as
[tex]p_f = m_w * v__{fw} } + m_b * v__{fb}}[/tex]
So [tex]v__{fw} }[/tex] is the final velocity of water which is zero due to the fact that when the water hits the block it losses its momentum and eventually the velocity becomes zero
So
[tex]5 = 2 * v__{fb }[/tex]
Thus [tex]v__{fb }} = \frac{5}{2}[/tex]
[tex]v__{fb }} = 2.5 \ m/s[/tex]
Thus
[tex]p_f = 2.5 * 2[/tex]
[tex]p_f = 5 \ kgm /s[/tex]
Now the average momentum change is
[tex]p_a = \frac{p_i +p_f}{2}[/tex]
[tex]p_a = \frac{5+5}{2}[/tex]
[tex]p_a =5 kgm/s[/tex]
Now the force acting on the block is
[tex]F = \frac{p_a }{t}[/tex]
and from the question the initial movement of the block took 1s as it is a mass of water moving at a rate of 1kg/s that caused the first movement of the block
So
[tex]F= \frac{5}{1}[/tex]
[tex]F= 5 \ N[/tex]
Now the acceleration is
[tex]a = \frac{F}{m_b}[/tex]
=> [tex]a = \frac{5}{2}[/tex]
[tex]a = 2.5 \ m/s^2[/tex]
"You throw a small rock straight up from the edge of a highway bridge that crosses a river. The rock passes you on its way down, 9.00 s after it was thrown. What is the speed of the rock just before it reaches the water 21.0 m below the point where the rock left your hand
Answer:
48.54 m/s
Explanation:
If the rock takes 9 seconds to reach your position after being thrown, it reaches its maximum height in 4.5 seconds.
The height the rock reaches above your position is ...
h = (1/2)gt^2 = (4.9 m/s^2)(4.5 s)^2 = 99.225 m
This height is an additional 21 m above the water, so the maximum height above the water is ...
99.225 m +21.0 m = 120.225 m
The velocity (v) achieved when falling from this distance is found from ...
v^2 = 2gh
v = √(2(9.8)(120.225)) = √2356.41 ≈ 48.543 . . . . m/s
The speed of the rock when it hits the water is about 48.54 m/s.
The main component of all computer memory is
Answer: R.A.M
Explanation:
1) Calculate the equivalent resistance of 2 resistors wired in parallel. The value of the resistors are
4 ohms and 8 ohms.
Explanation:
[tex]r = \: ( { \frac{4 \times 8}{4 + 8} } \\ r= \: ohm[/tex]2.67
Answer:2 2/3 ohms
Explanation:
equivalent resistance=R
r1=4 ohms
r2=8 ohms
For parallel connection
1/R=1/(r1) + 1/(r2)
1/R=1/4 + 1/8
1/R=(2x1+1x1)/8
1/R=(2+1)/8
1/R=3/8
Cross multiply
1x8=3xR
8=3R
Divide both sides by 3
8/3=3R/3
8/3=R
R=8/3 or 2 2/3 ohms
Newton's law of cooling states that the temperature of an object changes at a rate proportional to the difference between its temperature and that of its surroundings. Suppose that the temperature of a cup of coffee obeys Newton's law of cooling. If the coffee has a temperature of 210 degrees Fahrenheit when freshly poured, and 2.5 minutes later has cooled to 191 degrees in a room at 64 degrees, determine when the coffee reaches a temperature of 156 degrees.
Answer:
Explanation:
The problem is based on Newton's law of cooling .
According to Newton's law
dQ / dt = k ( T - T₀ ) ,
dT / dt = k' ( T - T₀ ) ; dT / dt is rate of fall of temperature.
T is average temperature of hot body , T₀ is temperature of surrounding .
In the first case rate of fall of temperature = (210 - 191) / 2.5
= 7.6 degree / s
average temperature T = (210 + 191) /2
= 200.5
Putting in the equation
7.6 = k' ( 200.5 - 64 )
k' = 7.6 / 136.5
= .055677
In the second case :---
In the second case, rate of fall of temperature = (191 - 156) / t
= 35 / t , t is time required.
average temperature T = (156 + 191) /2
= 173.5
Putting in the equation
35 / t = .05567 ( 173.5 - 64 )
t = 5.74 minute .
a 1200 kg trailer is hitched to a 1400 kg car. the car and trailer are traveling at 72 km.h when the driver applies the brakes on both the car and the trailer. knowing that the braking forces exerted on the car and the trailer are 5000 N and 4000 N respectively, determine (a) the distance traveled by the car and trailer before they come to a stop and (b) the horizontal component of the force exerted by the trailer hitch
Answer:
a) 8.67m
b) 1000N
Explanation:
(a) To find the distance you use the second Newton Law for both car and trailer, in order to calculate the dis-acceleration of the system:
[tex]F=ma\\\\a_=\frac{F}{m}=\frac{5000N+4000N}{1400kg+1200kg}=3.46\frac{m}{s^2}[/tex]
once you have this value, you use the the following kinematic equation to calculate the distance traveled by both car and trailer:
[tex]v^2=v_o^2-2ax\\\\x=\frac{-v^2+v_o^2}{2a}[/tex]
v: final velocity=0
vo: initial velocity = 72km/h = 60 m/s
by replacing the values of these parameters you obtain for x:
[tex]x=\frac{-0m/s+60m/s}{2(3.46m/s^2)}\\\\x=8.67m[/tex]
(b) The horizontal component of the force exerted by the trailer hitch is given by:
[tex]F_T=5000N-4000N=1000N[/tex]
When a star explodes as a supernova, the expanding gas can pass through the interstellar medium triggering...
A.) an increase in variable star activity
B.) formation of new stars
C.) life to develop
D.) additional supernovas
B. Formation of new stars
A person drives north 6 blocks, then turns west, and drives 6 blocks. The driver then turns south and drives 6 blocks. How could the driver have made the distance shorter while maintaining the same displacement?
Answer:
Considering that there is no obstructions, he could go west from the start.
Explanation:
A landscaper is shopping for landscaping materials. She wants to use materials through which water flows easily.
Which materials should she choose? Select three options.
clay
gravel
granite
rocks with cracks
loosely packed soil
Next
Mark this and retum
Save and Exit
Submit
Answer:
He needs clay gravel and rocks with cracks
A turntable has a moment of inertia of 3.00 x 10-2 kgm2 and spins freely on a frictionless bearing at 25.0 rev/min. A 0.300 kg ball of putty is dropped vertically on the turntable and sticks at a point 0.10m from the center. The total moment of inertia of the system increases, and the turntable slows down. But by what factor does the angular momentum of the system change after the putty is dropped onto the turntable
Answer:
There will be no change in the angular momentum of the system.
Explanation:
Total angular momentum of the system will remain unchanged . We can apply law of conservation of momentum because no external torque is acting on the system . There is increase in the momentum of inertia due to dropping of ball of putty . In order to conserve angular momentum , the system decreases its angular velocity . Hence the final angular momentum remains unchanged .
A three-phase Y-connected four-pole winding is installed in 24 slots on a stator. There are 40 turns of wire in each slot of the windings. All coils in each phase are connected in series. The flux per pole in the machine is 0.060 Wb, and the speed of rotation of the magnetic field is 1800 r/min. (a)What is the frequency of the voltage produced in this winding?(b)What are the resulting phase and terminal voltages of this stator?
Given Information:
Number of slots = 24
Number of turns = 40
Flux per pole = 0.060 Wb
Speed of rotation of magnetic field = 1800 rev/min
Required Information:
a) Frequency = ?
b) Phase and Terminal voltage = ?
Answer:
a) Frequency = 60 Hz
b) Phase voltage = 2560 V
Terminal voltage = 4434 V
Explanation:
(a)What is the frequency of the voltage produced in this winding?
The relation between frequency of the voltage produced and the speed of rotation of magnetic field is given by
[tex]f = \frac{nP}{120}[/tex]
Where n is the speed of rotation of magnetic field and P is the number of poles in the winding.
[tex]f = \frac{1800\times 4}{120}\\\\f = \frac{7200}{120}\\\\f = 60 \: Hz[/tex]
(b)What are the resulting phase and terminal voltages of this stator?
The phase voltage is given by
[tex]E = \sqrt{2} \cdot \pi\cdot N\cdot \phi\cdot f[/tex]
Where N is the number of turns, Ф is the flux per pole and f is the frequency calculated in part a.
[tex]E = \sqrt{2} \cdot \pi\cdot 40\cdot \ 0.060\cdot 60\\\\E = 639.77\\\\E = 640 \:V\\\[/tex]
There are total 24 slots so each phase has 24/3 = 8 slots
We know that the number of poles are 4 so that means each phase has 4 sets of coils.
So the voltage in each phase is
Vp = 4*640
Vp = 2560 V
Since it is a Y-connected machine, The terminal voltage is will be
[tex]V_T = \sqrt{3} V_p\\\\V_T = \sqrt{3} \cdot2560\\\\V_T = 4434 \: V\\\\[/tex]
When we apply the energy conversation principle to a cylinder rolling down an incline without sliding, we exclude the work done by friction because: A. there is no friction present B. the angular velocity of the center of mass about the point of contact is zero C. the coefficient of kinetic friction is zero D. the linear velocity of the point of contact (relative to the inclined surface) is zero E. the coefficient of static and kinetic friction are equal
Answer:
D. the linear velocity of the point of contact (relative to the inclined surface) is zero
Explanation:
The force of friction emerges only when there is relative velocity between two objects . In case of perfect rolling , there is no sliding so relative velocity between the surface and the point of contact is zero . In other words the velocity of point of contact becomes zero , even though , the whole body is in linear motion . It happens due point of contact having two velocities which are equal and opposite . One of the velocity is in forward direction and the other velocity which is due to rotation is in backward direction . So net velocity of point of contact becomes zero . Due to absence of sliding , displacement due to friction becomes zero . Hence work done by friction becomes zero.
A convex mirror of focal length 33 cm forms an image of a soda bottle at a distance of 19 cm behind the mirror.If the height of the image is 7.0 cm,where is the object located,and how tall is it? What is the magnification of the image? Is the image virtual or real? Is the image inverted or upright? Draw a ray diagram to confirm your results.
Answer:
Image distance = 44.8cm, Image height = 16.5cm, Magnification = 0.42
The image is a virtual and upright image.
Explanation:
The nature of image formed by an object placed in front of a convex mirror is always diminished, virtual and erect.
The focal length f and the image distance are always NEGATIVE beacause the image is formed behind the mirror.
Given f = -33.0cm, v = -19.0cm
using thr mirror formula to get the object distance u, we have;
[tex]\frac{1}{f}=\frac{1}{u} + \frac{1}{v}\\ \frac{1}{u}=\frac{1}{f} - \frac{1}{v}\\\frac{1}{u}=\frac{1}{-33} - \frac{1}{-19}\\\frac{1}{u}=\frac{-19+33}{627} \\\frac{1}{u}=\frac{14}{627} \\u=\frac{627}{14} \\u = 44.8cm[/tex]
To calculate the image height, we will use the magnification formula
M = [tex]\frac{image\ height}{object\ height}=\frac{image\ distance}{object\ distance} \\[/tex]
M = [tex]\frac{Hi}{HI}=\frac{v}{u}[/tex]
Given Hi = 7.0cm
v = 19.0cm
u = 44.8cm
HI = 7*44.8/19
HI = 16.5cm
The object height is 16.5cm
Magnification = v/u = 19.0/44.8 = 0.42
SInce the image is formed behind the mirror, the image is a VIRTUAL and UPRIGHT image
Can a moving object have gravitational energy?
Answer:
It is worth noting that the higher the gravitational energy of an object moving downwards, the lower the kinetic energy, and the lower the kinetic energy of an object moving upwards, the higher its gravitational energy.
Gravitational potential energy is acquired by an object when it has been moved against a gravitational field. For example, an object raised above the surface of the Earth will gain energy, which is released if the object is allowed to fall back to the ground.
Which of the following could possibly be predicted? Earthquakes Landslides Foreshocks Volcanic eruptions
Answer:
Volcanic Eruptions
Explanation:
The volcano can start showing signs that it may be about to explode.
Answer:
Volcanic eruptions.
Explanation:
I had the same question on an assignment and I got it right.
Eclipses of the sun and moon are best explained by which of the following?
The irregular shape of the orbits of Earth and the moon
The rotation of Earth and the moon on their axis
The revolution of Earth and the moon around the sun
The different chemical compositions of the sun and the moon
Answer:
Eclipses of the Sun and Moon are best explained by the revolution of Earth and the Moon around the Sun.
Explanation:
An eclipse is the covering of a star by another celestial body. In everyday language, an eclipse usually means a solar or lunar eclipse.
When the sun, moon and earth are aligned (in this order), the sun is covered by the moon when viewed from a place on earth. The sunlight will then no longer reach the earth. In other words, part of the earth has been eclipsed by the moon. This is referred to as a solar eclipse.
If the earth is between the sun and the moon, and thereby prevents sunlight from reaching the moon, then there is a lunar eclipse. After all, seen from the moon, the earth covers the sun. The moon is then eclipsed by the earth.
1. Deri had a large tank of oil (s-0.8) and was requested to determine the viscosity of that fluid. To assist with the process, she was given a 0.25-inch-diameter steel ball (sphere, s=8.0) to conduct the test. From the tests, she found that the terminal velocity of the sphere was 2.5 fpm. What is the viscosity of the oil? Remember, the volume of a sphere is (pi D3 /6). ANS. viscosity is 0.258 lb-s/ft2
Answer:
0.25916 lb-s/ft^2
Explanation:
Given:-
- The specific gravity of oil, SGo = 0.8
- The specific gravity of sphere, SGo = 8
- Terminal velocity of sphere, v = 2.5 fpm
- The diameter of sphere, D = 0.25 in
Find:-
What is the viscosity of the oil?
Solution:-
- Consider a sphere completely submerged into oil and travelling with terminal velocity ( v ).
- Develop a free body diagram for the sphere. There are forces acting on the sphere.
- The downward acting force is due to the weight of the sphere ( W ):
[tex]W = m_s*g[/tex]
Where,
The mass ( m_s ) of the sphere is given as:
[tex]m_s = S.G_s*p_w*V_s[/tex]
Where,
ρ_w : Density of water = 1.940 slugs/ft3
V_s: The volume of object ( sphere )
- The volume of sphere is expressed as a function of radius:
[tex]V_s = \frac{\pi *D^3}{6}[/tex]
Hence,
[tex]W = S.G_s*p_w*\frac{\pi*D^3 }{6}* g\\\\W = 8*1.940*\frac{\pi*(0.25/12)^3 }{6}*32\\\\W = 0.00235 lb[/tex]
- One of the upward acting force is the buoyant force ( Fb ) that is proportional to the volume of fluid displaced by the immersed object.
- The buoyant force ( Fb ) is given by:
[tex]F_b = S.G_o*p_w*V_s*g[/tex]
- Therefore the buoyant force ( Fb ) becomes:
[tex]F_b = 0.8*1.94*\frac{\pi*(0.25/12)^3 }{6} *32\\\\F_b = (4.73451*10^-^6)*(49.664)\\\\F_b = 0.00023 lb[/tex]
- The other upward acting force is the frictional drag ( F_d ) i.e the resistive frictional force acting on the contact points of the sphere and the fluid oil.
- From stokes formulations the drag force acting on a spherical object which is completely immersed in a fluid is given as:
[tex]F_d = 3*\pi*D*u*v[/tex]
Where,
μ: The viscosity of fluid
v : The velocity of object
Therefore,
[tex]F_d = 3*\pi*\frac{0.25}{12} *u*0.041666\\\\F_d = 0.00818*u\\[/tex]
- Apply Newton's second law of motion for the sphere travelling in the fluid:
[tex]F_n_e_t = m_s*a[/tex]
Where,
a: Acceleration of object = 0 ( Terminal velocity condition )
[tex]F_n_e_t = 0[/tex]
- Plug in the three forces acting on the metal sphere:
[tex]F_d + F_b - W = 0\\\\F_d = W - F_b\\\\0.00818*u = 0.00235 - 0.00023\\\\u = \frac{0.00212}{0.00818} = 0.25916 \frac{lb-s}{ft^2}[/tex]
Visible light travels in air, which has an index of refraction of 1.0. It is incident on plastic which is covered by a coating (such that light hits the coating before the plastic). The coating has an index of refraction of 1.6 and is 0.50 microns thick. The ray reflected off the air-coating interface and the ray reflected off the coating-plastic interface experience interference. What frequencies could the light be
Answer:
λ = 0.64 10⁻⁶ m = 640 nm
Explanation:
The two reflected rays experience constructive interference, if we can see them, so we can one condition for interference, but let's see two phenomena that occur
* A ray when it is reflected by a surface of major spare part index has a phase change of 180º, these passes at the air-plastic interface
* A ray when passing a material with a refractive index changes its wavelength
λ= λ₀ / n
taking into account these facts the condition in constructive interference is
2 n t = (m + ½) λ
λ= 2 n t / (m + ½)
if we suppose that we have the first inference m = 0
λ = 2 1.6 0.5 10⁻⁶ (0 + ½)
λ = 3.2 10⁻⁶ m
this wavelength is in the infrared
suppose an interference of m = 1
λ = 1.6 10⁻⁶ / (1 + 1/2)
λ = 1.06 10-6 m
m = 2
λ = 1.6 10⁻⁶ / (2 + 1.5)
λ = 0.64 10⁻⁶ m
this wavelength corresponds to the visible range (640 nm) orange
Which of the following is correct? When a current carrying wire is in your left hand, thumb in the direction of the magnetic field lines, your fingers point in the direction of the current. When a current carrying wire is in your left hand, thumb in the direction of the current, your fingers point in the direction of the magnetic field lines. When a current carrying wire is in your right hand, thumb in the direction of the magnetic field lines, your fingers point in the direction of the current. When a current carrying wire is in your right hand, thumb in the direction of the current, your fingers point in the direction of the magnetic field lines.
Answer:
When a current carrying wire is in your left hand, thumb in the direction of the magnetic field lines, your fingers point in the direction of the current
Explanation:
This is in line with the left hand rule
B.) When the current flows up the wire, the magnetic field flows out on the left side of the wire and in on the right side of the wire.
You could use an analytical or triple beam balance to determine a ___ called ____
A)
physical property; mass.
B)
chemical property, mass.
C)
physical property; weight.
D)
physical property; density.
Answer:
a and b are the correct answers
Explanation:
Answer:
A) physical property; mass.
Explanation:
took the test
the medium of a mechanical wave is the matter through wich it travels? tru or false
Answer:
it can only travel through matter
Explanation:
the mechanical wave can be any type of matter
A cylindrical specimen of some metal alloy having an elastic modulus of 108 GPa and an original cross-sectional diameter of 3.7 mm will experience only elastic deformation when a tensile load of 1890 N is applied. Calculate the maximum length of the specimen before deformation if the maximum allowable elongation is 0.45 mm.
Answer:
L= 276.4 mm
Explanation:
Given that
E= 180 GPa
d= 3.7 mm
F= 1890 N
ΔL= 0.45 mm
We know that ,elongation due to load F in a cylindrical bar is given as follows
[tex]\Delta L =\dfrac{FL}{AE}[/tex]
[tex]L=\dfrac{\Delta L\times AE}{F}[/tex]
Now by putting the values in the above equation we get
[tex]L=\dfrac{0.45\times 10^{-3}\times \dfrac{\pi}{4}\times (3.7\times 10^{-3})^2\times 108\times 10^9}{1890}\ m[/tex]
L=0.2764 m
L= 276.4 mm
Therefore the length of the specimen will be 276.4 mm
Now that you've done your research on the law of supply, you understand that it basically asserts that how much coffee you'd be willing to supply depends on how much money you can make for each cup.
Exercise should challenge your body and be at a greater intensity than your usual bif daily activity. Discuss
Answer:
A fan pushes hot air out of a vent and into a room. The hot air displaces cold air in the room, causing the cold air to move closer to the floor.
The hot air displacing the cold air is an example of transfer by
Explanation:
Which theory states that deviance results not only from what people do, but also from how others respond to those actions?
A.
strain theory
B.
labeling theory
C.
differential association theory
D.
control theory
E.
conflict theory
The theory states that deviance results not only from what people do but also from how others respond to those actions are labeling theory. Hence, the option B is correct.
What is labeling theory?This theory states that deviance and conformity result not so much from what people do but also from how others respond. It is called labeling theory. Eg: Skipping school, and underage drinking.
It also suggests that any deviance results in how society responds to certain behaviors. It defines the behavior of human beings influenced by other members of society.
It also notes that a person is made to act in a negative way by the manner in which society identifies him. If a person is identified as a criminal then he involves in the criminal activities.
Conflict theory refers to the theory linking deviance to social inequality. Anticipating the consequences of a person's behavior is control theory.
Hence, the correct option is B) labeling theory.
To learn more about the labeling theory:
https://brainly.com/question/31366596
#SPJ3
A potato and raisins salad has been warmed up to a temperature of 80∘C and let it stand for three minutes. Then one tries a bite. 1) Would the potatoes and raisins be equally warm? Potatoes have a specific heat of 3430 J/(kg⋅∘C). Raisins have a specific heat of 1630 J/(kg⋅∘C).
Answer:
No. Potatoes will be warmer.
Explanation:
[tex]Q=m\times c\times \Delta T[/tex]
where,
Q = heat taken
m = mass of substance
c = specific heat of substance = ?
ΔT = change in temperature
As we are given that the potatoes have a specific heat of 3430 J/(kg⋅∘C) and raisins have a specific heat of 1630 J/(kg⋅∘C). It implies that substance take more heat when higher the value of specific heat i.e more warmer will be the substance. Thus, the potatoes will be more warmer as compared to raisins.
Therefore, No. Potatoes will be warmer.
Which is a characteristic of diatoms?
A)whip-like tail
B)heterotrophic
C)multicellular
D)glass-ive cell wall
Answer:
b
Explanation:
Answer:
The correct answer is D, diatoms have glass-like cell walls.
Yellow light with wavelength 600 nm is travelling to the left (in the negative x direction) in vacuum. The light is polarized along the z direction. (a) Draw a neat snapshot mode labeled vector picture of the wave. (b) Draw a neat movie mode labeled vector picture of the wave. (c) If the wave were to represent blue light instead of yellow light, how would your pictures in parts a and b change? If there is no change, say so explicitly.
Answer: (a) and (b) => check attached file.
(c). Picture (a) and (b) will both remain the same.
Explanation:
IMPORTANT: The solution to the question (a) and (b) that is (a) Draw a neat snapshot mode labeled vector picture of the wave. (b) Draw a neat movie mode labeled vector picture of the wave is there in the ATTACHED FILE/PICTURE.
It is also worthy of note to know that in anything Electromagnetic wave, the magnetic field, the Electric Field and their direction of propagation are perpendicular to each other.
Therefore, knowing the fact above we can say that in yellow light, the magnetic field is in the y-direction and the Electric Field is in the z-direction.
Hence, the solution to option C is given below;
(C).If the wave were to represent blue light instead of yellow light, picture (a) will remain the same because both light are Electromagnetic wave, although the wavelength will have to change. Picture (b) will also remain the same because they are both Electromagnetic waves and possess similar properties.
Speed is the rate of change of position expressed as____ Traveled per unit of time
Answer:
distance
Explanation:
Speed is the rate of change of position expressed as distance travelled per unit of time
Dual Nature of Light
Assignment
Active
Explaining the Nature of Light
Why do scientists believe that light is made of streams of
particles?
Explain how an electrical current is produced.
Answer:electric current can be generated by moving a metal wire through a magnetic field .electric current can also be produced by batteries
Explanation:
electric current can be generated by moving a metal wire through a magnetic field.this method is applicable in electric generators.
Electric current can also be generated by connecting metal wires to batteries.
