Answer:
a) v = 0, a = - 15 pi²
b) v = - 40.8 cm / s, a = -74.2 cm / s
Explanation:
the simple harmonic motion is described by the expression
x = A cos (wt + Ф)
in that case they indicate the amplitude of the movement
A = 15 cm
angular velocity and period are related
w = 2π / T
w = 2π/ 2
w = π rad / s
speed is defined by
v = dx / dt
v = -A w sin (wt + Ф)
acceleration is defined by
a = dv / dt
a = - A w² cos (wt + Ф)
In order to evaluate this expression we must know the value of the phase constant (Ф) that meets the initial conditions, the most common thing is that the system is released, v = 0 for y = 0 s, let's use the speed equation
v = -A w sin (0+ Ф)
for this expression to be zero, the sine must be zero, so
Ф= 0
now let's write the equations for our case
v = - 15 π sin (π t)
a = - 15 π² cos (π t)
a) for x = 0
v = 0
a = - 15 pi²
b) for x = 7.5 cm
Let's find out how long it takes to get to this position
x = 15 cos (π t)
7.5 / 15 = cos π t
pi t = cos⁻¹ 0.5
t = 1.047/π
don't forget that the angles are in radians
t = 0.333 s
now let's look for speed and acceleration
v = - 15 π sin (π 0.333)
v = - 40.8 cm / s
a = - 15 π² cos (π 0.333)
a = -74.2 cm / s
Our entire ______ _____
is built in the backbone of metals.
Answer:
modern world
Explanation:
Help!!!
Where can the hoses be attached in order to provide water to a fire engine? (There may be more than one correct answer.)
house faucet
hydrant
generator
pumper truck
Answer:
Explanation:
Hydrant
a vehicle is moving with 20m/s towards the east and another is moving 15m/s towards the west
Answer:
5 m/s
Explanation:
Given that,
A vehicle is moving with 20m/s towards the east and another is moving 15m/s towards the west.
It is assumed to find the resultant velocity of the vehicle. Let east side is positive and west is negative. So,
[tex]v=v_1+v_2\\\\=20+(-15)\\\\=5\ m/s[/tex]
Hence, the resultant velocity of the vehicle is equal to 5 m/s.
Use Newton's second law of motion and a free-body diagram to...
1. ...calculate the normal force acting upon a 50-kg passenger who accelerates upward at a rate of 3.0 m/s/s.
2. ...calculate the normal force acting upon a 50-kg passenger who accelerates downward at a rate of 3.0 m/s/s.
Please don't put any links or I will report you.
Why does the golf ball sink in
water, while the beach ball
floats?
A- The beach ball weighs less than
the golf ball
B- The golf ball has a higher density
than the beach ball
C- The beach ball has a higher
density than the golf ball
D- The golf ball has more mass than
the beach ball
Bajo la acción del viento una puerta gira un ángulo de 90° en 5 s. Calcular su velocidad angular y la velocidad lineal de los puntos del borde
si el ancho de la puerta es de 50 cm. R. 0,314 rad/s, 0,157 m/s.
A child drops a bouncy ball. Each time it bounces, it reaches a lower height until it eventually
stops. Describe the energy transfers and explain why the ball lowered in height
Answer:
the ball's was lowered because of the gravitational force and because of the friction force's
When a substance is poured from one container to another, its shape changes but its volume does not, what state of matter is the substance in?
A. Plasma
B. Liquid
C. Gas
D. Solid
Answer: When a liquid substance is poured into a vessel, it takes the shape of the vessel, and, as long as the substance stays in the liquid state, it will remain inside the vessel. Furthermore, when a liquid is poured from one vessel to another, it retains its volume (as long as there is no vaporization or change in temperature) but not its shape.
Explanation: A solid has a definite shape and volume. A liquid has a definite volume, but takes the shape of its container. A gas lacks either a defined shape or volume. Plasma is similar to a gas in that its particles are very far apart, but a gas is electrically neutral and plasma has a charge.
Answer:
B
Explanation:
Liquid
Which is closest to the Earth?
A. Moon
B. Sun
C. Mars
D. Venus
Answer:
A. Moon
Explanation:
The Moon is hundreds of thousands of miles away from the Earth while the other options are hundreds of millions of miles away.
who is the first physicist and what did he invented?
Answer:
hippocrates
I guess..........
What type of specialized cell in the eye is used for detecting low levels of light?
Answer:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
Answer:
Rods
Explanation:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
A 20.0 Ohm and 60.0 Ohm resistor
are connected in series to a 9.00 V
battery. What is their equivalent
resistance?
(Unit = Ohms)
Answer:
for resistors in series, add the resistances to get their equivalence. The answer is
80.0 Ohms
providing trademark protection
Answer:
what are you asking exactly?
If you're the white mouse, what will you do in order for you to survive
Answer:
If I was the white mouse, I would either find somewhere to hide that matches my fur color to camoflouge with or dig into the dirt so less visible.
To find white colour habitat.
What will I do for my survival?If I was the white mouse, I would find white colour place for living because in that white colour the predators can't see me and i will be safe from them so we can conclude that finding white colour habitat is the best choice to safe myself.
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A 3kg object moving at 4 m/s encounters a 20 N resistive force over a duration of 0.20 seconds. The impulse experienced by this object is _____
Answer:
the impulse experienced by this object is 4 Ns
Explanation:
Given;
mass of the object, m = 3 kg
velocity of the object, v = 4 m/s
resistive force, F = 20 N
duration of impact, t = 0.2 s
The impulse experienced by this object is calculated as follows;
J = F x t
J = 20 x 0.2
J = 4 Ns
Therefore, the impulse experienced by this object is 4 Ns
A specified volume of space contains an electric field for which the magnitude is given by E=E0cos(ωt). Suppose that E0 = 20 V/m and ω = 1.0 × 107 s−1. What is the maximum displacement current through a 0.40 m2 cross-sectional area of this volume?
Answer: [tex]0.708\ mA[/tex]
Explanation:
Given
[tex]E_o=20\ V/m[/tex]
[tex]\omega =10^7\ s^{-1}[/tex]
Cross-sectional area [tex]A=0.40\ m^2[/tex]
Current density is given by
[tex]J=\epsilon_o \dfrac{dE}{dt}[/tex]
Displacement current
[tex]\Rightarrow I=JA\\\Rightarrow I=8.854\times 10^{-12}\times 20\times 10^7\times 0.4\\\Rightarrow I=0.708\times 10^{-3}\ A[/tex]
The required value of the maximum displacement current of the given space is [tex]7.08 \times 10^{-4} \;\rm A[/tex].
Given data:
The intensity of electric field is, [tex]E_{0}=20 \;\rm V/m[/tex].
The angular frequency of electric field is, [tex]\omega=1.0 \times 10^{7} \;\rm s^{-1}[/tex].
The cross-sectional area of space is, [tex]A =0.40 \;\rm m^{2}[/tex].
In the given problem, the instantaneous electric field is given by [tex]E = E_{0} \times cos(\omega t)[/tex]
So, the expression for the current density is,
[tex]J= \epsilon_{0} \times \dfrac{dE}{dt}[/tex]
Here, [tex]\epsilon_{0}[/tex] is the permittivity of free space. Solving as,
[tex]J= \epsilon_{0} \times \dfrac{d(E_{0} \times cos(\omega t))}{dt}\\\\J= -\epsilon_{0} \times E_{0} \times \omega \times sin(\omega t)[/tex]
And the expression for the maximum displacement current is,
[tex]I = J \times A[/tex]
And the maximum displacement current is possible only when, J is positive and J will be positive for [tex]sin(\omega t)=-1[/tex].
Then solving as,
[tex]I = (-\epsilon_{0} \times E_{0} \times \omega \times sin(\omega t)) \times A\\\\I = (-8.85 \times 10^{-12} \times 20 \times (1.0 \times 10^{7}) \times (-1)) \times 0.40\\\\I = 7.08 \times 10^{-4} \;\rm A[/tex]
Thus, we can conclude that the required value of the maximum displacement current of the given space is [tex]7.08 \times 10^{-4} \;\rm A[/tex].
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If a body is thrown up with an initial velocity 'u' and covers a maximum height of 'h' , then 'h' is equal to u²/2g
Explain in detail.
Answer:
1/2 m u^2 initial Kinetic Energy of body
m g h Potential Energy body attains as it rises to height
1/2 m u^2 = m g h conversion of KE to PE
h = u^2 / ( 2 g)
An electromagnet is a device that uses an electric current to produce a magnetic field.
Electromagnets are typically composed of a piece of metal wrapped with wire and connected to a battery. The battery provides the electric current, and the loops or coils of wire enhance the magnetic field. The more loops there are, the stronger the magnetic field.
When electric current flows through the electromagnet, the metal core becomes magnetized, so it possesses a north pole and a south pole.
Motors place electromagnets inside of permanent magnets as shown below.
However, motors are designed so that the polarity of the electromagnet constantly flips. That is, the north pole becomes the south pole, and the south pole becomes the north pole, every time the electromagnet turns 180 degrees.
Why is it designed this way?
A.
to conserve the energy in the battery
B.
to constantly polarize the field magnet
C.
so the electromagnet will continuously turn
D.
so the magnetic field will get stronger
The reason why motors are designed so that the polarity of the electromagnet constantly flips.is
C. so the electromagnet will continuously turn
Why is motor designed that wayThe reason motors are designed so that the polarity of the electromagnet constantly flips is to continuously turn the electromagnet. This allows the motor to rotate continuously, rather than becoming stuck in one position.
The flipping of the polarity causes the electromagnet to attract and repel from the permanent magnets, creating a rotating motion.
Therefore, the correct answer is C.
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Which of these statements explains why we have day and night? [1] The Earth orbits the Sun once a day The Sun orbits the Earth once a day. The Sun spins on its axis once a day. The Earth spins on its axis once a day.
Answer:
The Earth spins on its axis once a day.
Explanation:
In simple words,The Earth revolves on its axis once every 24 hours and circles the sun once every 365 days. The Earth's rotation on its axis, not its orbit throughout the sun causes day as well as night. The word 'one day' refers to the period it requires the Earth to spin entirely on its axis, which involves both day as well as night.
What is only found in plant cells??
Cell membrane , nucleus, cell wall , vacuole.
which one !!!
You slide out of a car seat and as you touch the metal door a spark jumps between your hand and the door. Describe how the spark formed
Answer: Your body sliding against the car seat created friction, making it created potential energy. The friction is a form of electricity, and the car doors metal is a conductor of electricity. That potential energy was turned into kinetic once the metal attracted the electricity, thus making a spark.
Hope this helps ^_^
How much work is done when 300 N of force is used to lift the dog 1.5 m?
Answer:
450N
Explanation:
Work done=Force*distance
How is it possible a plant can sustain itself for 70 years locked inside a jar ?
Answer:
If you are talking about the experiment in which mouse and plants are kept in a closed glass jar in sunlight so in that case, they both survive because the CO2 released by the respiration of mouse is being utilized by the plants and fixed ( phosynthesis) and O2 is released as by product, which is taken by the mouse for respiration.
define one ampere current electricity
Determine the resistance of 100m of copper cable whose cross-sectional area is 1.5mm2
In a symbiotic relationship,
a. one organism benefits while its host gets nothing in return.
b. bacteria takes food from your stomach, but does nothing for you.
c. both organisms involved benefit or are neutrally affected.
d. your body produces vitamins and then uses them for nutrition
In a symbiotic relationship, both organisms involved benefit or are neutrally affected. Symbiosis is a close and long-term interaction between two different species.
The term "symbiosis" encompasses mutualism, commensalism, and parasitism. In mutualism, both organisms benefit from the interaction, such as in the case of bees and flowers where bees obtain nectar and pollen while also helping flowers to pollinate.
In commensalism, one organism benefits while the other is neither helped nor harmed, such as remora fish that attach to sharks for transportation and feeding on scraps left by the shark. In parasitism, one organism benefits while the other is harmed, such as ticks that feed on blood from a host animal.
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Can someone please help me with history.
Answer:
Yes my name is Axelrod I can help you
Which type of comb would be best to use in the winter, a plastic comb or a glass comb? Explain using the Triboelectric series.
Answer:
I'm not sure how to use it using the Series, but it would be the plastic comb
Explanation:
In the winter, it's likely to be cold and the glass would absorb that energy, also making it cold. in order to be able to hold it, you would need something warm, thus making the plastic one the better option as it is less likely to absorb the cold energy
2. Give at least 2 major roles of mining in our lives.
Answer:
Mined materials are needed to construct roads and hospitals, to build automobiles and houses, to make computers and satellites, to generate electricity, and to provide the many other goods and services that consumers enjoy.
Explanation:
True or False. The Magnitude of the induced voltage in a coil of wire depends on how quickly the magnetic flux through the coil of wire changes.
Answer:
Yes, its true
Explanation:
hdheheishdhieijzuwhs
Answer: yes its true
Explanation:
nmo
