What happens when two polarizers are placed in a straight line, one behind the other?
A. They allow light to pass only if they are polarized in exactly the same direction.
B. They block all light if they are polarized in exactly the same direction.
C. They allow light to pass only if their directions of polarizations are exactly 90° apart.
D. They block all light if their directions of polarizations are exactly 90° apart.
E. They block all light If their directions of polarizations are either exactly the same or exactly 90° apart.
Match the following. Column A 1. Torque 2. Centre of gravity 3. Plumb line Column B A. Line of centre of gravity B. Maximum constant velocity C. Not in motion D. Point of action of weight E. Turning effect of force F. Study of forces 4. Terminal velocity 5. Statics
Answer:
1. Torque → F. Study of forces
2. C.O.G → D. Point of action of weight.
3. Plumb line → A. Line of C.O.G
What is the pH when just enough ammonia solution is added to react with all the nitric acid?
Answer:
<7
Explanation:
This is a reaction between a steong acid and a weak base which produces a acidic salt at equvalence point. Hence pH is less than 7
help me with this please
Answer:
Family
1. Definition of a family
A family is a group of people living together in a home related by blood, marriage or adoption.
2. Two function of the family are;
socialization for the children in the family.love and happiness should be in a family for it to be function.3. Two types of family are;
Single parent family- this family includes one parent and his or her child, we can say it's an incomplete family.nuclear family- this family includes the two parents and their children or child, this family is known as the complete family.4. Two roles and responsibilities of the parents and children in the home are;
both parents must and should protect their child or children from harm.the children must have respect for the family.Accident in the Home
1. Definition of accident in the home
accidents in the home are common to persons of all ages, therefore home accidents occurs in one's home that may cause an result an injury of a person
2. Two types of accident in the home
fallsminor cuts and wounds3. The two uses of cereals in cooking
Cereals in cooking are used as thickened agents.
4. complete table
1. minor cuts and wounds
Causes: these are caused by broken glasses, contact with sharp instruments such as knife, pins and needles.Prevention: this can be prevented by keeping the Sharp tools in safe places after used2. Poisoning
Causes: poisoning can caused by in a result from children taking tablets for sweets, which can lead to death.preventions: you can prevent this by avoiding poisoning from the from the home or you could put it at a safe place that you know the child cannot get it.Care labels
1. definition of care label
care labels can be defined as a permanent label or we can say a tag, which contains regular instructions that is attached at the back of a cloth.
3. two classification of carbohydrates
Monopolywhy does mass decrease when acceleration increases?
Answer:
Since the mass does not change as the acceleration increases, we can say that force is equal to acceleration. Therefore, if you double the force you double the acceleration. If you increase the mass at a given force the rate of acceleration slows. Therefore, mass is inversely proportional to acceleration.
pls someone should help me answer question 3. Thank you
Answer:
(a) 12 m/s
(b) At t = 0, x'(t) = 0
At t = 5.0 s, x'(t) = 15 m/s
At t = 10.0 s, x'(t) = 12 m/s
(c) i. The initial velocity = 2.0 cm/s
The initial position = 50 cm
The initial acceleration = 0.125 cm/s²
ii. 16 seconds
2. (a) Approximately 0.85 m/s
(b) 2.094 J
(c) i. Approximately 49.74 m/s
ii. Approximately 86.38°
3. (i) 4·i + 5·j
(ii) -2·i - j - 2·k
(iii) 5·i + 4·j - 3·z
(iv) 8
(v) (a) The magnitude is 2.8 cm, the direction is East
(b) The magnitude is ((14·√3)/5) cm, the direction is North
(c) The magnitude is ((14·√3)/5), the direction is South
Explanation:
x(t) is given as follows;
x(t) = b·t² - c·t³
Where;
b = 2.4 m/s(²) (we note that the unit of b for the term to be distance in m/s²)
c = 0.120 m/s³
(a) At t = 0, we have;
x(0) = b × 0² - c × 0³ = 0
At t = 10.0 s, we have;
x(10.0) = 2.4 m/s² × (10.0 s)² - 0.120 m/s³ × (10.0 s)³ = 120 m
The average velocity = (Total distance)/(Total time)
∴ The average velocity of the car for the time interval t = 0 to t = 10.0 s, [tex]v_{ave}[/tex], is given as follows;
[tex]v_{ave}[/tex] = (120 m - 0 m)/(10.0 s - 0 s) = 12 m/s
The average velocity of the car for the time interval t = 0 to t = 10.0 s, [tex]v_{ave}[/tex] = 12 m/s
(b) The instantaneous velocity, [tex]v_{inst}[/tex], is given as follows;
[tex]v_{inst} = \lim \limits_{t \to 0} \left( v_{ave}\right) = \lim \limits_{t \to 0} \left( \dfrac{\Delta x}{\Delta t} \right) = \dfrac{dx}{dt} = x'(t)[/tex]
[tex]x'(t) = \dfrac{d\left (b \cdot t^2 - c \cdot t^3\right)}{dt}[/tex]
x'(t) = 2·b·t - 3·c·t²
At t = 0, x'(t) = 2 × b × 0 - 3 × c × 0² = 0
At t = 5.0 s, x'(t) = 2 × 2.4 m/s² × 5.0 s - 3 × 0.120 m/s³ × (5.0 s)² = 15 m/s
At t = 10.0 s, x'(t) = 2 × 2.4 m/s² × 10.0 s - 3 × 0.120 m/s³ × (10.0 s)² = 12 m/s
(c) x(t) = 50 cm + (2.0 cm/s)·t - (0.0625 cm/s²)·t²
i. The initial velocity is the instantaneous velocity, x'(t), at time, t = 0
x'(t) = 2.0 cm/s - 2 × 0.0625 cm/s² × t
At t = 0, x'(0) = 2.0 cm/s - 2 × 0.0625 cm/s² × 0 = 2.0 cm/s
The initial velocity, x'(0) = 2.0 cm/s
The initial position = The position at time t = 0 = x(0)
x(0) = 50 cm + (2.0 cm/s) × 0 - (0.0625 cm/s²) × 0² = 50 cm
The initial position, x(0) = 50 cm
The initial acceleration, x''(0) = 2 × 0.0625 cm/s² = 0.125 cm/s²
ii. x'(t) = 2.0 cm/s - 2 × 0.0625 cm/s² × t
When the velocity of the turtle, x'(t) = 0 we have;
0 = 2.0 cm/s - 2 × 0.0625 cm/s² × t
∴ t = (2.0 cm/s)/(2 × 0.0625 cm/s²) = 16 seconds
The velocity of the turtle is zero after 16 seconds
2. The mass of the large fish, m₁ = 15.0-kg
The speed of the large fish, v₁ = 1.1 m/s
The mass of the smaller fish, m₂ = 4.50 kg
The speed of the small (stationary) fish, v₂ = 0
The initial momentum = 15.0 kg × 1.1 m/s + 4.50 kg × 0 = 16.5 kg·m/s
The initial momentum = 16.5 kg·m/s
The final momentum = (15.0 kg + 4.50 kg) × v₃ = 19.50 kg × v₃
The final momentum = 19.50 kg × v₃
Where;
The total initial momentum = The total final momentum
We get;
16.5 kg·m/s = 19.50 kg × v₃
∴ v₃ = (16.5 kg·m/s)/(19.50 kg)
v₃ = (16.5/19.50) m/s = (11/13) m/s ≈ 0.85 m/s
∴ The speed of the large fish just after it eats the small, v₃ ≈ 0.85 m/s
(b) The initial kinetic energy, K.E.₁ = (1/2) × 15 kg × (1.1 m/s)² = 9.075 J
The final kinetic energy, K.E.₂ = (1/2) × 19.5 kg × (11/13 m/s)² = 363/52 J
The mechanical energy dissipated, ΔE = K.E.₁ - K.E.₂
ΔE = (9.075 - 363/42) J = 1089/520 J ≈ 2.094 J
The mechanical energy dissipated, ΔE = 2.094 J
(c) i. We have the total momentum = 110 × 8.8· j + 85 × 7.2· i = 9.680·i + 612·i
The velocity after collision, v = (9.680·i + 612·i)/(110 + 85) = 49.64·j + 3.14·i
The magnitude of the velocity, v = √(49.64² + 3.14²) ≈ 49.74 m/s
ii. The direction, θ = arctan(49.64/3.14) ≈ 86.38°
3. (i) [tex]\underset{A}{\rightarrow} + \underset{B}{\rightarrow}[/tex] = (i + 2·j - k) + 3·i + 3·j + k = 4·i + 5·j
(ii) [tex]\underset{A}{\rightarrow} - \underset{B}{\rightarrow}[/tex] = (i + 2·j - k) - (3·i + 3·j + k) = -2·i - j - 2·k
(iii) [tex]\underset{A}{\rightarrow} \times \underset{B}{\rightarrow}[/tex] = (2 + 3)·i - (1 + 3)·j + (3 - 6)·z = 5·i + 4·j - 3·z
(iv) [tex]\underset{A}{\rightarrow} \cdot \underset{B}{\rightarrow}[/tex] = 1×3 + 2 × 3 + (-1)×1 = 8
(v) (a) [tex]\underset{A}{\rightarrow} + \underset{B}{\rightarrow}[/tex] = 2.8·cos(60°)·i + 2.8·sin(60°)·j + (2.8·cos(60°)·i - 2.8·sin(60°)·j
[tex]\underset{A}{\rightarrow} + \underset{B}{\rightarrow}[/tex] = 5.6·cos 60°·i = 2.8·i
The magnitude = 2.8, the direction is east
(b) [tex]\underset{A}{\rightarrow} - \underset{B}{\rightarrow}[/tex] = 2.8·cos(60°)·i + 2.8·sin(60°)·j - (2.8·cos(60°)·i - 2.8·sin(60°)·j
[tex]\underset{A}{\rightarrow} - \underset{B}{\rightarrow}[/tex] = 5.6·sin(60°)·j= ((14·√3)/5)·j
The magnitude = ((14·√3)/5), the direction is North
(c) [tex]\underset{B}{\rightarrow} - \underset{A}{\rightarrow}[/tex] = (2.8·cos(60°)·i - 2.8·sin(60°)·j - (2.8·cos(60°)·i + 2.8·sin(60°)·j)
[tex]\underset{B}{\rightarrow} - \underset{A}{\rightarrow}[/tex] = -5.6·sin(60°)·j= (-(14·√3)/5)·j
The magnitude = ((14·√3)/5), the direction is South
Tính hiệu suất nhiệt của động cơ nhiệt biết nhiệt lượng ở nguồn nóng 420,4kJ/kg và nhiệt lượng ở nguồn lạnh 218kJ/kg.
Answer:
69
Explanation:
just because
The frequency of a note played on a piano is 262 Hz. Given that the velocity of sound at 20°C is 343 m/s, what is the wavelength of the note?
Answer:
Explanation:
The equation for frequency is
[tex]f=\frac{v}{\lambda}[/tex] where
f = frequency, v is velocity, and lambda is wavelength. Filling in:
[tex]262=\frac{343}{\lambda}[/tex] and
[tex]\lambda=\frac{343}{262}[/tex] so
[tex]\lambda=1.31m[/tex]
The wavelength of the note played on the piano is 1.31m.
Given the data in the question;
Frequency of the note played on a piano; [tex]f = 262Hz = 262s^{-1}[/tex]Velocity; [tex]v = 343m/s[/tex]Wavelength of the note; [tex]\lambda = \ ?[/tex]
WavelengthWavelength is simply referred to as the spatial period of a periodic wave i.e when the shapes of waves are repeated, the distance over which they are repeated is called wavelength. It is expressed as;
[tex]\lambda = \frac{v}{f}[/tex]
Where v is velocity and f is frequency
We substitute our given values into the expression above;
[tex]\lambda = \frac{v}{f} \\\\\lambda = \frac{343m/s}{262s^{-1}} \\\\\lambda = 1.309m\\\\\lambda = 1.31m[/tex]
Therefore, the wavelength of the note played on the piano is 1.31m.
Learn more about wavelength: https://brainly.com/question/16776907
one of the rectangular components of the velocity 40ms^1 is 20 ms^1. find the other components
Answer:
The other component is 17.32m/s.
For more information
lemme so you how to solve it!
given velocity v = 20 m/s
let the given rectangular component is
cos somponent, so 10 = v cos x
so, other component will be sin component
i.e., v sin x
or, 10 = 20 cos x
or, cos x = 1/2
and as sin^2 x + cos^2 x = 1
or, 1 - cos^2 x = sin^2 x
or, 1 - (1/2)^2 = sin^2 x
so, sin x = sqrt( 1 - 1/4)
or, sin x = sqrt(3/4)
so, rectangular component is
20 sin x = 20 sqrt(3/4)
= 10 sqrt3
= 17.32 m/s
Explanation:
hope to help you (:
when baking soda is added to a solution of citric acid, the temperature of the solution drops.
Answer:
i dont know guy sorry ha babu
a baseball player hits a ball with 400 n of force.how much does the ball exert on the bat
Answer:
The ball exerts a force of 400 N on the bat.
Explanation:
Given that,
A baseball player hits a ball with 400 N of force.
We need to find the force the ball exert on the bat.
We know that,
According to Newton's third law, when object 1 exerts a force on an object 2, then object 2 will exert a force on object 1 but in opposite direction.
So, the ball exerts a force of 400 N on the bat.
Which of the following are
matter?
Chair, air, love, smell, hate,almonds, thought, cold, cold-drink, smell of perfume.
Answer:
everything except smell,hate,love,cold
Answer:
chair, air, almonds, cold-drink, smell of perfume
Explanation:
Anything that occupies space and has mass is called matter. Matter can exist in three physical states which are the:
Solid state
Liquid state
Gaseous state
therefore:
Solids: chair and almonds
Liquids: cold-drink
Gas: air and smell of perfume
•Love, smell, hate, thought, and cold are not in the category of matter/are not considered matter
•The sense of smell is not considered a form of matter. However, the smell or odour of a substance is classified as matter.
-The smell of any substance (say, perfume) is the gaseous form of that substance our olfactory system can detect (even at deficient concentrations).
Hence, the smell of some substances is considered matter.
Use the universal law of gravitation to solve the following problem.
The force of gravity between Jake and his daughter Annika is 1.67 × 10–9 N. If they are 11 m apart and Jake has a mass of 110 kg, what is Annika's mass?
a. Write out the formula for this problem.
b. Plug in the values from this problem into the formula.
c. Solve the problem, writing out each step.
d. Correct answer
Answer:
Explanation:
Formula
Force = G * m1 * m2 / r^2
Givens
F = 1.67 * 10 - 9 NG = 6.67 × 10-11 Newtons kg-2 m2.m1 = 110 kgm2 = ?r = 11 meters.Solution
1.67 * 10^-9 = 6.67 * 10^-11 * 110 * m2/(11)^2 Divide both sides by 10^-9
1.67 * 10^-9/10^-9 = 6.67*10^-11/(10^-9 *110*m2/121
1.67 = 6.67 * 110 * 10^-2 * m2 / 121 Multiply both sides by 121
1.67 * 121 = 6.67 * 10 ^-2 * 110 * m2 * 121/121 Combine
202.07 = 7.337 * m2 Divide both sides by 7.337
202.07/7.337 = m2
m2 = 27.54 kg
Two balls collide head-on in a perfectly inelastic collision. The first ball has a mass of 0.75 kg and an initial velocity of 5.0 m/s to the right. The second ball has a mass of 0.40 kg and an initial velocity of 3.5 m/s to the left. What is the decrease in kinetic energy during the collision?
Explanation:
Momentum conservation
V=3.38
Delta kinetic energy =1/2m(vi^2-v^2)
A partially inflated balloon is faded over the open end of a glass beaker that contains water the beaker is placed in an ice bath which cause the water and causes the balloon to the flea what are the correct designs for the heat and work changes to the beaker and balloon system
Answer:
a
Explanation:
Eratosthenes measured the circumference of Earth to within 4% of the correct value
A. Looking at stick shadows on the equinox.
B. Noting how much more of the celestial sphere came into view when walking south.
C. Sighting the stars from within the deepest well in Egypt on the day of the solstice.
D. Using the detailed reports of far-sailing mariners
Answer:
A. Looking at stick shadows on the equinox.
Explanation:
He measures the circumference by placing a pole when the sun is overhead on the days of solstice. He determined the circumference by measuring the difference between Alexandria to Syene and the angle of the pole's shadow.
The equation used for the calculation of circumference is as follow
[tex]\frac{360 degrew}{7.2 degree} = \frac{Circumference of earth}{Distance from Alexandria to Syene}[/tex]
Please refer to the following link for more details
https://www.khanacademy.org/humanities/big-history-project/solar-system-and-earth/knowing-solar-system-earth/a/eratosthenes-of-cyrene
please I need the answer right now will mark you brainliest
Answer:
Explanation:
what do u need help with
Answer:
that's for frequency other answers are coming soon
When do we have positive/negative and zero acceleration.Write down the terms..................pls help mee
Answer:
Positive acceleration is when an object is increasing its velocity, speeding up.
Negative acceleration is when an object is decreasing its velocity, slowing down from it’s motion.
Zero acceleration is when an object is either at rest or moving without speeding up or slowing down, in a constant way.
Two friends are working out together using weights:
-James lifts 20kg weights up at a velocity of 1.9m/s
-Kayla lifts 15kg weights up at a velocity of 2.6m/s
0
Which friend is creating more momentum?
Answer:
Kayla. You can calculate it using the formula for momentum: momentum=mass×velocity and find the bigger number between the two momentums
Planets A and B have the same size, mass, and direction of travel, but planet
A is traveling through space at half the speed of planet B. Which statement
correctly explains the weight you would experience on each planet?
A. You would weigh the same on both planets because their masses
and the distance to their centers of gravity are the same.
B. You would weigh more on planet B because it is traveling twice as
fast as planet A.
C. You would weigh the same on both planets because your mass
would adjust depending on the planet's speed.
D. You would weigh less on planet B because it is traveling twice as
fast as planet A.
Answer:
A. You would weigh the same on both planets because their masses and the distance to their centers of gravity are the same.
Explanation:
Given that Planets A and B have the same size, mass.
Let the masses of the planets A and B are and respectively.
As masses are equal, so .
Similarly, let the radii of the planets A and B are and respectively.
As radii are equal, so .
Let my mass is m.
As the weight of any object on the planet is equal to the gravitational force exerted by the planet on the object.
So, my weight on planet A,
my weight of planet B,
By using equations (i) and (ii),
.
So, the weight on both planets is the same because their masses and the distance to their centers of gravity are the same.
Hence, option (A) is correct.
which is heavier a kilogram of iron or a kilogram of feathers?
Answer:
they both weight the same
Explanation:
they both weigh one kilo so they are the same
On Earth, 1 kg weighs 9.8 Newton's.
Doesn't matter what substance it's a kg of.
Describe the difference between a sidereal day and a solar day.
Answer:
a sidereal day is the time it takes for the earth to rotate about it axis so that the distant star appears In the same position in the sky while a solar day is the time it takes for the earth to rotate about it axis so that the sun appears in the same position in the sky
Dont have a question rn
Answer:
you have gay
Explanation:
699999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999ooooooooooooooooooooooooooo
Answer:
Answer: C. -12 newtons
Explanation: Since, the block is in static equilibrium,
the net force on the block is zero i.e. balance forces are acting on the block.
In the horizontal direction,
force applied+force due to friction = 0
20 N + (-20N) = 0
In the vertical direction as well, net force is zero:
Force due to gravity + force exerted by the ground = 0
12 N + force exerted by the ground = 0
⇒force exerted by the ground = 0 -12 N = -12 N
Thus, the correct option is C. -12 N where negative sign means that the direction of the force due to ground is opposite to the force of gravity.
I WILL GIVE BRAINLY
1. Describe the electromagnet’s field. What pattern/connection do you see? Explain.
Explanation:
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pa brainliest po thanks❤
What is Meaning of Registration
Answer:
Theres 2 meanings first is:
the action or process of registering or of being registered.
The other one is:
a combination of stops used when playing the organ.
The meaning of registration is the action of process of registering to some applications or websites which includes some terms and conditions also.
What is registration?Registration is the process or action of registering into a website or application or to any institute through online or offline mode. By registering we are giving some personal and professional details as per the requirements of the source which need us to be registered.
For example, if we are applying for a central examination, we have to register our name and details in the official website of the examination board.
The registration process bring us some terms and conditions which we can apply or accept to continue the registration process. After successful registration we can have an acknowledgement for the action.
Find more on registration process:
https://brainly.com/question/29602320
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Given the following information, in which medium is the velocity of light the highest?
What is centripetal force? A. A force acting parallel to the path of an object in circular B. A force opposing motion along a circular path C. A force acting away from the center of a circular motion D. A force acting toward the center of a circular motion
Answer:
c.
Explanation:
Answer:
Centripetal force is the force acting towards the center of circular motion or path.
[tex]{ \tt{formular : \: F = \frac{m {v}^{2} }{r} }} \\ { \tt{F : \: is \: centripetal \: force}} \\ { \tt{m : \: is \: mass}} \\ { \tt{v : \: is \: velocity}} \\ { \tt{r : \: is \: radius}}[/tex]
Explanation:
Its opposite is centrifugal force which acts away from the center of circular path.
A constellation’s changing position in the sky, at the same time of the evening, over a period of several weeks is evidence that:
a- Earth is round b- Earth’s axis is tilted. c- Earth rotates on its axis.
d- Earth revolves around the sun.
Answer:
d- Earth revolves around the sun.
Explanation:
Earth rotation can be defined as the amount of time taken by planet earth to complete its spinning movement on its axis.
This ultimately implies that, the rotation of earth refers to the time taken by earth to rotate once on its axis. One spinning movement of the earth on its axis takes approximately 24 hours to complete with respect to the sun.
On the other hand, earth revolution can be defined as a complete trip along a path around the sun. This path is known as an orbit and it typically takes the Earth 365¼ days to complete it's journey around the Sun.
When a constellation (stars) changes its position in the sky, at the same time of the evening and over a period of several weeks; it ultimately implies or is an evidence that Earth revolves around the sun.
" When the apple falls,does the apple also attract the earth?
Answer:
yes
Explanation:
masses attract each other
with a teeny-tiny force
please help me ..im begging you
Explanation:
let's assume that:
v1= 600ml=0,6l
T1=27°C= 300K
p1=700mmHG=93326Pa
T2=-20°C=253K
p2=500mmHg=66661
V2=?
p1V1/T1=p2V2/T2 => V2=p1V1T2/p2
V2= 93326*0,6*253/66661
V2=212,52l