Explanation:
Given,
Position vector, [tex]c(t)=6ti+((3t)^2)j+((t)^3)k[/tex]
We need to find the velocity vector of the given path
[tex]v=\dfrac{d(c(t))}{dt}\\\\v=\dfrac{d(6ti+((3t)^2)j+((t)^3)k)}{dt}\\\\v=\dfrac{d(6ti)}{dt}+\dfrac{d((3t)^2j}{dt}+\dfrac{d(t^3)k}{dt}\\\\v=6i+18tj+3t^2k[/tex]
Hence, this is the velocity vector of the given path.
As it heats, does fluid rise or compact
s
Answer: The fluid would rise.
Find the order of magnitude of your age in seconds. 1)10^3 s 2)10^6 s 3)10^9 s 4)10^12 s
B) Estimate the number of times your heart beats in a month.
1)10^2 2)10^4 3)10^6 4)10^8
C) Estimate the number of human heart beats in an average lifetime.
1)10^5 2)10^7 3)10^9 4)10^11
Answer:
A) 3, B) 3, C) 3
Explanation:
The order of magnitude is a very useful unit for when you do not have a precision in the measurement, the way to find it is to take the number to scientific notation and then change the whole part to 101 if it is greater than or equal to five or 10 or less than five
A) take my age to seconds
for example if I am 25 years old.
I take the years to seconds
age = 20 years (365 day / year) (24 h / 1 day) (3600 s / 1h)
age = 630720000 s
we carry scientific notation
age = 6.3072 10⁸ s
as the integer greater than five we change it by 10¹
age = 10⁹s
The correct answer is 3
B) The number of beats per minute approximately 80 beats in a month we have
# beats = 80 beats /min (60min / 1h) (24 h / 1 day) (30 day / 1 month)
# _beats = 3456000 beats / month
#_beats = 3,456 10⁶ beats / month
as the integer is less than five we change it by 10⁰
#_beats = 10⁶
the correct answer is 3
C) the number of heartbeats in life
suppose a life expectancy of 80 years
#_beats_total = 80 pulse /min (60min / 1h) (24 h / 1day) (365 day / year) 80 year
#_total_beats = 3 363 840 000
#_beats_total = 3.36384 10⁹
as the integer is less than five we change it by 10⁰
#_beats_total = 10⁹
the correct answer is 3
An archer fires an arrow straight up into the air with a speed vo = 29 m/s. Neglect air resistance.Required:a. FInd the Maximum height h reached by the arrow, in meters.b. What is the mass of the car plus its occupants in kg?
Answer:
42.9 m.
Explanation:
The following data were obtained from the question:
Initial velocity (v₀) = 29 m/s
Acceleration due to gravity (g) = 9.8m/s²
Maximum height (h) =.?
The maximum height reached can be obtained by using the following formula:
H = v₀² /2g
Where:
H is the maximum height reached.
v₀ is the initial velocity.
g is the acceleration due to gravity.
H = v₀² /2g
H = (29)² / (2 × 9.8)
H = 841 / 19.6
H = 42.9 m
Therefore, the maximum height reached by the arrow is 42.9 m
Tammy jogged 350 meters at a velocity of 7 m/s. How long did it take her to jog this distance?
Answer:
50 seconds
Explanation:
divide 350 by 7...
add my tik(tok) slapddaddy
Select the correct answer. Which sentence about particles in matter is true? A. Atoms are present in solids and liquids but not in gases. B. The particles of matter are in constant motion. C. The same kinds of atoms are found in different elements. D. When a solid changes to a liquid, the sizes of the particles change.
Answer:
B : The particles of matter are in constant motion
Explanation:
Use metric conversion factors to solve each of the following problems:a. If a student is 175 cm tall, how tall is the student in meters?b. A cooler has a volume of 5000 mL. What is the capacity of the cooler in liters?c. A hummingbird has a mass of 0.0055 kg. What is the mass, in grams, of the hummingbird?d. A balloon has a volume of 3500 cm3. What is the volume in liters?
Answer:
a) 1.75 m
b) 5 L
c) 5.5 g
d) 3.5 L
Explanation:
a) cm -> m
1 m = 100 cm, so,
1 cm = 1/100 m
175 cm = 175/100 m
175 cm = 1.75 m
b) mL -> L
1 L = 1000 mL, so
1 mL = 1/1000 L
5000 mL = 5000/1000 L
5000 mL = 5 L
c) kg -> g
1 g = 1/1000 kg, so
1 kg = 1000 g
0.0055 kg = 0.0055 * 1000 g
0.0055 kg = 5.5 g
d) cm³ -> L
1 L = 1000 cm³, so
1 cm³ = 1/1000 L
3500 cm³ = 3500/1000 L
3500 cm³ = 3.5 L
therefore, we can conclude that 175 cm is 1.75 m, 5000 mL is 5 L, 0.0055 kg is 5.5g and 3500 cm³ is 3.5 L
Answer:
Explanation:
Answer:
a) 1.75 m
b) 5 L
c) 5.5 g
d) 3.5 L
Explanation:
a) cm -> m
1 m = 100 cm, so,
1 cm = 1/100 m
175 cm = 175/100 m
175 cm = 1.75 m
b) mL -> L
1 L = 1000 mL, so
1 mL = 1/1000 L
5000 mL = 5000/1000 L
5000 mL = 5 L
c) kg -> g
1 g = 1/1000 kg, so
1 kg = 1000 g
0.0055 kg = 0.0055 * 1000 g
0.0055 kg = 5.5 g
d) cm³ -> L
1 L = 1000 cm³, so
1 cm³ = 1/1000 L
3500 cm³ = 3500/1000 L
3500 cm³ = 3.5 L
therefore, we can conclude that 175 cm is 1.75 m, 5000 mL is 5 L, 0.0055 kg is 5.5g and 3500 cm³ is 3.5 L
Coulomb's Law: Two identical small charged spheres are a certain distance apart, and each one initially experiences an electrostatic force of magnitude F F due to the other. With time, charge gradually diminishes on both spheres by leaking off. When each of the spheres has lost half its initial charge, what will be the magnitude of the electrostatic force on each one?
Answer:
The magnitude of electrostatic force on each charge is quarter of the magnitude of initial electrostatic force. ( ¹/₄ F)
Explanation:
The electrostatic force between two charges is given by Coulomb's law;
[tex]F = \frac{kQ_1Q_2}{r^2}[/tex]
where;
Q₁ and Q₂ are the magnitude of the charges
r is the distance between the charges
k is Coulomb's constant
Since the charges are identical;
Q₁ = Q
Q₂ = Q
the electrostatic force experienced by each charge is given by;
[tex]F = \frac{kQ^2}{r^2}[/tex]
When each of the spheres has lost half of its initial charge;
Q₁ = Q/2
Q₂ = Q/2
[tex]F_2 = \frac{k(Q/2)(Q/2)}{r^2}\\\\ F_2 = \frac{k(Q)(Q)}{4r^2}\\\\F_2 = \frac{1}{4} (\frac{kQ^2}{r^2} )\\\\F_2 = \frac{1}{4} (F)[/tex]
Therefore, the magnitude of electrostatic force on each charge is quarter of the magnitude of initial electrostatic force.
The velocity of sound is generally greater in solids than in gases at NTP. Why?
Answer:
Because they are so close, than can collide very quickly, i.e. it takes less time for a molecule of the solid to 'bump' into its neighborough. Solids are packed together tighter than liquids and gases, hence sound travels fastest in solids.
Which expression represents the sum of 8 and twice a number
8+n
8+2n
8×2n
2×(8+n)
Answer:
8 + 2 n (second expression listed)
Explanation:
Since we don't know the number, we represent it with a letter (n).
Twice a number (two times that number) will therefore be: 2 n.
and the addition (sum) of 8 to such will lead to 8 + 2 n
The sum of 8 and twice a number is : 8 + 2 n
Joelle is a manager at a construction company, and she is interested in the chemistry behind the materials they use. She has begun studying the materials used to fill walls. She knows that to keep the temperature inside a room steady the material must be a thermal insulator, and she predicts that materials should not be acidic or else they would dissolve too easily in water. Which is most likely a molecule in a wall-filling material? C6H6 Na6Ba6 NeNa HCl
Answer:
C6H6
Explanation:
I just took the test.
The only compound in the given options that is not soluble in water at normal condition is benzene (C₆H₆).
The material used in the wall-filling cannot be acidic or acidic salts. Acids and acidic salts have the tendency to dissolve in water.
An acid salt is a type of salt that can produce an acidic solution when it dissolves in water or other solvents.
In given compounds we can eliminate the possible acids and acid salts or water soluble compounds.
compounds of sodium are soluble in water (eliminate Na₆Ba₆ and NeNa)Hcl is acid which will dissolve in waterThus, the only compound in the given options that is not soluble in water at normal condition is benzene (C₆H₆).
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Cell phones require powerful batteries in order to work effectively. Which
activity is best described as an engineering endeavor related to cell-phone
batteries?
A. Designing an investigation that will help determine where the
materials used to make them can be found
B. Performing experiments to explain how different materials used in
batteries store energy
O C. Developing a plan to convince cell-phone companies to use their
batteries
D. Improving their design to make it easier to recycle them when they
are no longer useful
The activity D. Improving their design to make it easier to recycle them when they are best described as an engineering endeavor related to cell phone batteries.
What is an engineering endeavor related to the generation of a product?An engineering endeavor related to the generation of a product can be defined as any type of solution in order to enhance a particular feature of a given product, thereby increasing its utility in order to maximize the process that leads to its use by the clients of such product and or service in the market.
Endeavor engineering generally is based on the combination between extensive discovery and product development in order to solve a particular issue related to the product.
Therefore, with this data, we can see that an engineering endeavor related to the generation of a product is aimed at enhancing a particular feature of such a product.
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3. Will a plant grow higher with more light?
a. Hypothesis + Prediction:
b. Independent Variable (IV):
c. Dependent Variable (DV):
d. Controlling Variable (CV):
e. Experiment:
Answer:
When we analyze the sentence we see that this is a hypotype with the growth of plants must behave and it has a prediction included.
Therefore the correct answer is a
Explanation:
In this exercise you are asked to identify the given sentence with a specific part of the scientific method.
Among the parts of the method we have.
* Independent variable . The controlled variable in research
*Dependent variable. The magnitude measured in the experiment
* Control variable. The magnitude that is not controlled
*Experiment. It is the design of the procedure to evaluate the hypothesis
* Hypothesis. It is the assumption with which scientific work begins
* Prediction. It is a consequence of work if the mortgage is correct.
When we analyze the sentence we see that this is a hypotype with the growth of plants must behave and it has a prediction included.
Therefore the correct answer is a
A 50 mm diameter thin walled pipe is covered with an insulation layer with thicknessof 25mm and thermal conductivity of0.075W/mK. The inner pipe carries a superheated vapor at atmospheric pressure. The steam temperature entering the pipe is 120°Candthe air temperature is 20°C. The convection heat transfer coefficient on top of the insulation layer is 15W/m(K. If the velocity of the steam is 10 m/s, at what point along the pipe the steam starts to condense?
Answer:
The steam will start to condense at 6.6 mm into the pipe
Explanation:
The volume flow rate =π×(50/1000)²/4×10 = 0.0196 m³/s
The specific volume of the steam = 1.769 m³/kg
Therefore;
The mass flow rate = 0.0196/1.769 = 0.011099 kg/s
The resistance of the insulation material = ln(0.075/0.05)/(2×π×0.075) = 0.860 K/W
The resistance of the outside film of the insulator = 1/(15×2×π×0.075×1) = 0.14147 K/W
The total resistance = 0.14147 + 0.860 = 1.00147 K/W
1/(UA) = 1.00147 K/W
A = 2×π×0.05×1
1/U = 0.3146
U = 3.178 W/m² K
We have;
T(x) = T₀ + (Tin - T₀) exp(-UπDx/mcp)
Therefore, when T(x) = 100°C, we have;
100 = 20 + (120 - 20)exp(-3.178×π×0.05x/(0.011099 × 1.33))
Solving, we get
x = 6.597× 10⁻³ m ≈ 6.6 mm
Therefore, the steam will start to condense at 10 mm into the pipe.
Bryan Allen pedaled a human-powered aircraft across the English channel from the cliffs of Dover to Cap Gris-Nez on June 12, 1979. He flew for 169 minutes at an average velocity of 3.53 m/s in a direction 45.0∘ degrees south of east. Allen encountered a headwind averaging 2.00 m/s almost precisely in the opposite direction of his motion relative to the earth. What was his average velocity relative to the air?
Answer:
The answer is "[tex]5.53 \ \frac{m}{s}[/tex]"
Explanation:
apply the formula for calculating the average velocity to the relative air
[tex]V_{PG} =V_{PA}+V_{AG}[/tex]
[tex]\Rightarrow V_{PA} = V_{PG} -V_{AG}[/tex]
Given value:
[tex]V_{AG} = -2 \ \frac{m}{s}[/tex]
[tex]V_{PG} =3.53[/tex]
[tex]\Rightarrow V_{PA} = 3.53 - (-2) \\\\\Rightarrow V_{PA} = 3.53 +2 \\\\\Rightarrow V_{PA} = 5.53 \\\\[/tex]
The final answer is "[tex]5.53 \ \frac{m}{s}[/tex]" in the south-east direction.
A positive and a negative charge are released from rest in vacuum. They move toward each other. As they do: A positive and a negative charge are released from rest in vacuum. They move toward each other. As they do: A negative potential energy becomes less negative. A positive potential energy becomes a negative potential energy. A positive potential energy becomes more positive. A negative potential energy becomes more negative. A positive potential energy becomes less positive. SubmitRequest Answer
Answer:
A negative potential energy becomes more negative
Explanation:
Let the charges be - Q₁ and Q₂ . Let the distance between them be d .
Potential energy = k -Q₁x Q₂ / R
= - KQ₁ Q₂ / R
Now if the magnitude of R decreases , the magnitude of potential energy increases . So we see that the negative potential energy becomes more negative .
Of the following, which change in motion took the greatest amount of time?
es )
A)
A ball falling at 73 m/s and hitting the ground at 9.8 m/s?
B)
An object speeding up from 64 m/s to 129 m/s at an acceleration of 9.8
m/s2
A horse slowing from a 90 m/s velocity to a 38 m/s velocity at an
acceleration of 8.2 m/s2
A car slowing down at an acceleration of 5.6 m/s from a speed of 45 m/s
to a speed of 9 m/s.
D
Answer:
A. A ball falling at 73 m/s and hitting the ground at 9.8 m/s
Explanation:
The equation for accleration is a= ▲v/▲t With a final velocity of 0 m/s minus the initial 73 m/s, at an acceleration of 9.8 m/s^2, the ball would take 7.45 seconds to hit the ground.
Lab reporton motin please help me answer all queastions 1-11 thank you
Answer:
yor welcome
Explanation:
hi
What does the big bang theory suggest
Answer:
The Big Bang Theory is the leading explanation about how the universe began. At its simplest, it says the universe as we know it started with a small singularity, then inflated over the next 13.8 billion years to the cosmos that we know today.
Explanation: Hope this help! :)
A train moves from rest to a speed of 25 m/s in 50.0 seconds. What is its acceleration?
Answer:
Wellll. I am assuming the direction of speed is in the same direction as the direction of displacement of the train. (i.e. Velocity is positive)
Acceleration is defined as the rate of change of velocity with respect to time (m^s-2)
Explanation:
A ball is thrown straight up and passes point B (at a height of 56.8 m above its starting point O) in 5.8 s. What was its initial speed? The acceleration of gravity is 9.8 m/s 2 . Answer in units of m/s
Answer:
38.2 m/s
Explanation:
Given:
Δy = 56.8 m
a = -9.8 m/s²
t = 5.8 s
Find: v₀
Δy = v₀ t + ½ at²
56.8 m = v₀ (5.8 s) + ½ (-9.8 m/s²) (5.8 s)²
v₀ ≈ 38.2 m/s
For an object that experiences constant non-zero acceleration, V f = V i
True or False
Answer:false
Explanation:
Determined to test gravity, a student walks off the Burj Khalifa (aka really tall building) in Dubai, which is
829 m high, and falls freely. His initial velocity is zero. Jetpack Woman leaves the roof 5 s later to save
the student with an initial velocity downward and then is in free-fall. In order both to catch the student
and to prevent injury to her, Jetpack Woman should catch the student at a sufficiently great height and
arrive at the ground with zero velocity. The upward acceleration that accomplishes this is provided by
Jetpack Woman's jet pack, which she turns on just as she catches the student; before then the student is
in free-fall. To prevent discomfort to the student, the magnitude of the acceleration is limited to four
times gravity (4 G). (You may assume that Jetpack Woman has superpowers, which allow her to change
velocity instantaneously.) How high above the ground must Jetpack Woman catch the student?
Answer:
y = 165.8 m
Explanation:
This is an exercise in kinematics that we must solve in parts,
Let's start with the final part where we have more data, the final velocity of the student and jet is zero, the upward acceleration is
a = 4g = 4 9.8 = 39.2 m /s²
Let's find the initial velocity and the height
v² = v₂² + 2 a y
0 = v₂² + 2 ay
2ay = - v₂²
v₂² = 2a y
Let's write the equation for the first part
student
v₂² = v₀² - 2 g (y₀ -y)
in this case the student jumps v₀ = 0
v₂² = 2 g (y₀ -y)
the total height is y₀ = 829 m
let's solve the system of equations by equating
2ay = 2 g (y₀ -y)
2a y = 2 g y₀ - 2g y
2 y ( g + a) = 2 g y₀
y = yo g/(g +a)
a= 4 g
y = yo 1/5
calculate
y = 829 /5
y = 165.8 m
A bus is moving at a speed of 20 m/s, when it begins to slow at a constant rate of 5 m/s2 in order to stop at a bus stop. If it comes to rest at the bus stop, how far away was the bus from the stop?
Answer:
u=20m/sec
v=0
a=5m/sec^2
v^2=u^2-2as[ here acceleration is negative]
0=400-2x5xs
-400= -10s
s= 40 metre.
The bus stop is 40 m away from the point at which it starts to slow down at -5 m/s².
State third equation of motion?
The third equation of motion is -
v² - u² = 2aS
Given is a bus moving at a speed of 20 m/s. It begins to slow at a constant rate of 5 m/s² in order to stop at a bus stop.
We can write -
[u] = 20 m/s
[a] = - 5 m/s²
[v] = 0 m/s
Using the third equation of motion -
v² - u² = 2aS
- (20)² = 2 x - 5 x S
- 400 = - 10 S
S = 400/10
S = 40 m
Therefore, the bus stop is 40 m away from the point at which it starts to slow down at -5 m/s²
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The angle of deflection shows the amount of electric force on each balloon. A greater force causes the balloon to deflect to a greater angle. Since the two balloons are deflected to the same angle, we know that the force on each balloon must be the same. Why do you think the balloons have the same amount of force exerted on them?
Answer:
Hello the options to your question is missing attached below are the missing options
Electrical forces are symmetrical, The electric repulsion of the Balloons is equal because electric forces between two objects are always symmetricalThe electric forces are equal in this case because both balloons had the same amount of electric chargeAnswer :
Electrical forces are symmetrical, The electric repulsion of the Balloons is equal because electric forces between two objects are always symmetrical
Explanation:
The Balloons have the same amount of force exerted on them, because Electrical forces are symmetrical, The electric repulsion of the Balloons is equal because electric forces between two objects are always symmetrical, therefore the two Balloons are deflected to the same angle
A ferry is travelling at 10 m/s relative to the river towards the south. The river is flowing at 2 m/s relative to
the riverbank towards the south. If a passenger on the ferry walks towards the rear of the ferry (north) at 1.0
m/s, what is their velocity relative to the riverbank?
Answer:
11 m/s south
Explanation:
The velocity of the passenger relative to the river bank is equal to the velocity of the passenger relative to the ferry, plus the velocity of the ferry relative to the river, plus the velocity of the river relative to the river bank.
v_passenger,bank = v_passenger,ferry + v_ferry,river + v_river,bank
If we take north to be positive and south to be negative:
v = 1.0 m/s + (-10 m/s) + (-2 m/s)
v = -11 m/s
v = 11 m/s south
Use the mass and volume data to calculate the density of liquid propane to the nearest hundredth. Mass of propane = 4,300 g Volume of propane = 10,000 mL The density of liquid propane is g/mL
Answer:
0.43
Explanation:
because i said it was
Answer:
0.43
Explanation:
Because he said it was (and yes it is right)
You are working on a laboratory device that includes a small sphere with a large electric charge Q. Because of this charged sphere, there is a strong electric field surrounding your device. Other researchers in your laboratory are complaining that your electric field is affecting their equipment. You think about how you can obtain the large electric field that you need close to the sphere but prohibit the field from reaching your colleagues. You decide to surround your device with a spherical transparent plastic shell. The nonconducting shell is given a uniform charge distribution. Required:a. The shell is placed so that the small sphere is at the exact center of the shell. Determine the charge that must be placed on the shell to completely eliminate the electric field outside of the shell. b. What if the shell moves? Does the small sphere have to be at the center of the shell for this scheme to work?
Answer:
the only effect it has is to create more induced charge at the closest points, but the net face remains zero, so it has no effect on the flow.
Explanation:
We can answer this exercise using Gauss's law
Ф = ∫ e . dA = [tex]q_{int}[/tex] / ε₀
field flow is directly proportionate to the charge found inside it, therefore if we place a Gaussian surface outside the plastic spherical shell. the flow must be zero since the charge of the sphere is equal induced in the shell, for which the net charge is zero. we see with this analysis that this shell meets the requirement to block the elective field
From the same Gaussian law it follows that if the sphere is not in the center, the only effect it has is to create more induced charge at the closest points, but the net face remains zero, so it has no effect on the flow , so no matter where the sphere is, the total induced charge is always equal to the charge on the sphere.
Select all that apply.
A chemist is likely to do which of the following?
analyze the ingredients in ice cream
determine why planets orbit the Sun
determine how to separate gasoline from other substances in petroleum
determine the force necessary to push a button through a button hole
Answer:
Determine how to separate gasoline from other substances in petroleum
A cue stick has a mass of 0.5 kg. The cue stick hits a ball with a mass of 0.2 kg at a velocity of 2.5 m/s. What is the velocity of the ball after it is hit?
Answer:
1 m/s.
Explanation:
Given that,
Mass of a cue stick, m₁ = 0.5 kg
Mass of a ball, m₂ = 0.2 kg
The cue stick hits a ball with a velocity of 2.5 m/s
We need to find the velocity of the ball after it is hit. Tn this problem, the momentum of the system remains conserved. So,
m₁v₁ = m₂v₂
⇒ [tex]v_1=\dfrac{m_2v_2}{m_1}\\\\v_1=\dfrac{0.2\times 2.5}{0.5}\\\\v_1=1\ m/s[/tex]
So, the velocity of the ball after it is hit is 1 m/s.
Answer:
The moment of impact quick check (connexus academy)
Explanation:
Q.Which mathematical representation correctly identifies impulse?
A.impulse=force×time
Q.In a closed system, a ball with a mass of 3 kg and a momentum of 24 kg·m/s collides into a ball with a mass of 1 kg that is originally at rest. Which statement describes the momentum of the balls and the total momentum?
A.The momentum of each ball changes, and the total momentum stays the same.
Q.In a closed system, three objects have the following momentums: 110 kg⋅m/s, −65 kg⋅m/s, and −100 kg⋅m/s. The objects collide and move together. What is the total momentum after the collision?
A.−55 kg⋅m/s
Q.In a closed system, an object with a mass of 1.5 kg collides with a second object. The two objects then move together at a velocity of 50 m/s. The total momentum of the system is 250 kg⋅m/s. What is the mass of the second object?
A.3.5 kg
Q.A cue stick has a mass of 0.5 kg. The cue stick hits a ball with a mass of 0.2 kg at a velocity of 2.5 m/s. What is the velocity of the ball after it is hit?
A.6.3 m/s
A mass on a string of unknown length oscillates as a pendulum with a period of 1.8 s. What is the period in the following situations? (Parts (a) to (d) are independent questions, each referring to the initial situation.)(a) The mass is doubled?(b) The string length is doubled?(c) The string length is halved?(d) The amplitude is doubled?
Answer:
Using
Period ( P) is given as
P~√(L/g).
a) since mass has no effect on the period of a pendulum. So, the period will remain 1.8seconds
b) using the formula above ,period varies with the square root of the length. Thus , when the length doubles, the period is multiplied by √2. So, the period is 1.8s*√2 = 2.54s
c) in this case, the period is multiplied by √(1/2).
1.8√(1/2)=1.27s.
d) amplitude of the pendulum doesn't affect the period (unless itsvery high, so, the period is still 1.8s
