Answer:
4
Explanation:
4-3
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.
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
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.
Given the following information, in which medium is the velocity of light the highest?
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
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
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
Your friend has informed you that his/her uncle has decided not to look after him anymore.Write to your friends uncle giving him at least two reasons why he should change his mind
Answer:
Cause you are their family and they need you. Do you wanna be someone who abandoned them or be the one they look to and dont dislike into adulthood. Also you signed onto this job no one said it was going to be easy but you making your life easier but harder for someone who is just a kid who still needs you.
This ray diagram shows the image formed when a candle is placed in front of
a curved mirror. Which of the following describes the image?
A. Virtual; smaller than object
B. Real; larger than object
C. Virtual; larger than object
D. Real; smaller than object
Answer:
Explanation:
Virtual images are always right side up while real images are always upside down. Therefore, the is a virtual image that is smaller than the original.
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.
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 (:
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)
why 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.
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.
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
#SPJ2
how can one add vectors and subtract vectors
Answer
Explanation:
Simple arithmetic cannot be used if two or more vectors are not along the same direction. Vectors can be added when two vectors are in the same direction but for the subtraction of vectors, if the vectors are not in the same direction you then subtract.
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
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.
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
name the device of measurement and write its used or its function?
Answer:
There is a lot of instruments used for measurement, may I ask which one are you referring to?
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
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
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
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.
Which best compares radiation and conduction?
C Both transfer thermal energy from warm objects to cooler objects.
O Both can transfer energy through empty space.
O Both transfer thermal energy by electromagnetic waves.
O Both involve the transfer of energy through direct contact.
Answer:
The statements that best compares radiation and conduction are the following: both transfer thermal energy from warm objects to cooler objects and both can transfer energy through matter. The difference is that conduction is through direct heat transfer; whereas, radiation transfers heat through waves.
interconversion of states of matter
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.
" When the apple falls,does the apple also attract the earth?
Answer:
yes
Explanation:
masses attract each other
with a teeny-tiny force
I WILL GIVE BRAINLY
1. Describe the electromagnet’s field. What pattern/connection do you see? Explain.
Explanation:
sana po nakatulong
pa brainliest po thanks❤