Answer:
The velocity at that time would be [tex](-67.975\; \rm s)[/tex]. The velocity of this particle is continuously changing.
Explanation:
Differentiate the expression for position [tex]x[/tex] with respect to time [tex]t[/tex] to find an expression for velocity.
[tex]\begin{aligned}v(t) &= \frac{d}{dt}[x(t)] \\ &= \frac{d}{dt} \left[ 7.4 + 9.2\, t - 2.1\, t^{3}\right]\\ &= 9.2 - 6.3\, t^{2}\end{aligned}[/tex].
Hence, at [tex]t = 3.5\; \rm s[/tex], velocity would be [tex]v(3.5) = 9.2 - 6.3 \times (3.5)^{2} = -67.975\; \rm m[/tex].
Since velocity [tex]v(t)[/tex] changes with time [tex]t[/tex], the velocity of this particle is continuously changing.
Rearrange this equation so it equals d
v=dt
Answer:
Below
Explanation:
To solve for d rearrange the formula v = (d)(t) to:
d = v / t
I'm not to sure if you are using different variables but usually in physics the formula for velocity is v = d / t not v = dt
If you wanted to solve for displacement you would do:
d = (v)(t)
Hope this helps!
is work the same as power justify the statement
Answer: No
Explanation: Simply Power’s Si base unit is kgm^2s^-3 but work done‘s Si base unit is kgm^2s^-2.
So this itself proves that they arent the same!
select the correct relationship of the densities of the given substances: !●water < iron < aluminium < mercury ● Iron < water < mercury < aluminium ● water < aluminium < iron < mercury ● none of the above. asap plz!!!
Answer:
option a is correct
Explanation:
water ∠iron∠aluminium∠mercury
water density =1.0000
iron =7.487
aluminium=2.07
mercury=13.59
what is the shape of the line graph that shows the temperature change over time of the liquid before it starts to boil?
The line graph showing the temperature change over time of a liquid before it boils has an upward-sloping trend as heat is applied until it reaches its boiling point, with fluctuations due to heat transfer rate changes.
What is the heat transfer rate?Heat transfer rate refers to the amount of heat energy transferred per unit of time between two objects or substances that are at different temperatures. It is a measure of how quickly heat is transferred between two objects or substances and is influenced by factors such as the temperature difference between the objects, the thermal conductivity of the materials, the surface area in contact, and the type of heat transfer mechanism involved (conduction, convection, or radiation). Heat transfer rate is often expressed in units of watts or BTUs per unit of time (e.g., watts/second or BTUs/hour).
Here in the Question,
The shape of the line graph that shows the temperature change over time of the liquid before it starts to boil is generally an upward-sloping line. As heat is applied to the liquid, its temperature will increase gradually until it reaches its boiling point. The rate of temperature increase may not be constant, and there may be some fluctuations due to factors such as changes in the rate of heat transfer.
Therefore, the trend of the line graph will be upward-sloping until the liquid reaches its boiling point.
To learn more about the boiling point of water click:
https://brainly.com/question/30462611
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What is one Pascal pressure? What is its unit?
Explanation:
the force acting perpendicularly on unit area of surface
unit=pascle .
A pressure of one Newton per square meter .. The SI unit of 1 Pascal pressure is 1 Newton per square metre .
Bonds Quick Check
Metallic bonds are responsible for many properties of metals, such as conductivity. Why is this possible? (1 point)
A Metals have low electronegativity, so they are conductive because they pass charges easily.
Two metals bonded together are going to be more conductive than a metal bonded with a
nonmetal
C An attraction between a positive charge and a negative charge is created.
The bonds can shift because valence electrons are held loosely and move freely.
Answer: The bonds can shift because valence electrons are held loosely and move freely.
Explanation:
what is system? Define
Answer:
a system is a set of some things which helps the good happenings in ousr day to day life. It also helps the astrophysisists to find the planets with a system
1. The first stage of stellar formation is the assembly (or formation) of a_______ . 2. Stars form in clouds. 3. When a cloud collapses it into smaller and smaller pieces till those pieces reach stellar masses. 4. As the density increases, the fragments become_______ , which________ the temperature of the cloud and inhibits further fragmentation. 5. The _______then condense into rotating globs of gas that serve as stellar embryos. 6. During this stage the surface temperature_______ and luminosity_________ despite decreasing size. 7. The central temperature and pressure increase as the potential energy is converted to energy due to contraction.
Answer: The keywords to input into the blank spaces were omitted which are ; fragments, increases, decreases, opaque, raises, molecular, protostar, gravitational, thermal.
Please find the answers for the blank spaces in the explanation column
Explanation:
1. The first stage of stellar formation is the assembly (or formation) of a_PROTOSTAR______ . 2. Stars form in MOLECULAR clouds. 3. When a cloud collapses, it FRAGMENTS into smaller and smaller pieces till those pieces reach stellar masses. 4. As the density increases, the fragments become_OPAQUE______ , which___RAISES_____ the temperature of the cloud and inhibits further fragmentation. 5. The __FRAGMENTS_____then condense into rotating globs of gas that serve as stellar embryos. 6. During this stage the surface temperature INCREASES_______ and luminosity__INCREASES_______ despite decreasing size. 7. The central temperature and pressure increase as the GRAVITATIONAL potential energy is converted to energy due to THERMAL contraction.
The above describes the evolution or formation of stars which begins with the collapse of a molecular cloud by gravitational force, this collapse cause the molecular cloud to fragment with the release of heat --Gravitation potential energy causing an increased temperature and pressure of the newly condensing fragment with increasing luminosity known as a Protostar.
A round steel plate with a diameter of 20 cm is supplied with heat in such a way that its temperature changes from 22 ° C to 150 ° C. How much does its area increase?
Answer:
1.05×10⁻⁴ m²
Explanation:
ΔA = 2 A₀ α ΔT,
where ΔA is the change in area,
A₀ is the initial area,
α is the linear expansion coefficient,
and ΔT is the change in temperature.
A₀ = π (0.20 m / 2)² = 0.0314 m².
For steel, α = 13×10⁻⁶ /°C.
ΔT = 150°C − 22°C = 128°C.
ΔA = 2 (0.0314 m²) (13×10⁻⁶ /°C) (128°C)
ΔA = 1.05×10⁻⁴ m²
the scientist who gives the definition of work
Answer:
Work, in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. ... To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd.
What is a hypothesis?
A. A piece of information gathered during an experiment
OB. A source that summarizes a primary source
O C. Something that a scientist intentionally changes during an
experiment
O D. An educated guess about the outcome of an experiment
Answer:
D!!!!!
Explanation:
A hypothesis is a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
Answer:
D. An educated guess about the outcome of an experiment.
Explanation:
Hypothesis is an educated guess about the outcome of an experiment.
Hope this helps ;) ❤❤❤
Which units represent density? Select all that apply.
Answer:
D=M/V. That's the formula. Density is expressed, in cubic centimeters.
Explanation:
Answer:g/m³
g/cm³
-kg/L
-kg/cm³
Density in physics, is defined as the mass of the object over its volume. Density is considered as how much matter is contained in a single object by its volume or the matter that it occupies.
D = m / v
Explanation:
If the N pole of a magnet is brought near to an unmagnetized iron, nail, then the nail becomes
Answer:
The nail also magnatized .
how do you find average velocity
Answer:
find the sum of the inital and final velocitys and divide by 2 to find the average
define 1 second time
Answer:
define 1 second time
One second is the time that elapses during 9,192,631,770 (9.192631770 x 10 9 ) cycles of the radiation produced by the transition between two levels of the cesium 133 atom. ... One second is equal to 1/86,400 of a mean solar day.
Answer:
One part of 86400 part of a day is called one second time.
✌✌✌✌
3 bulbs are in series and the same 3 bulbs are in parallel with the same battery. Which bulbs will be dimmer?
A. The same
B. Parallel
C. Series
D. Not enough info
Answer:
Explanation:
The series three. The series 3 will cut the voltage into 1/3. The current will also be lower because of the voltage drop.
The parallel circuit will not cut the voltage and the current will be tripled because each bulb is taking out exactly what it needs.
As an aside, house wiring would be a nightmare if the bulbs were connected in series. If one bulb burned out, you'd have to find it in the dark because they all would go out.
20 pts. What type of forces do not change the motion of an object? Acceleration forces Balanced forces Inertia forces Unbalanced forces
Answer:
Balanced forces
Explanation:
Answer:
its balance force
Explanation:
An average skater averages 11 m/s over the first 5 seconds of a race. find the average speed required over next 10 seconds to average 12 m/s overall.
Answer:
usa
Explanation:
A liquid will evaporate more.....at a lower temperature
A liquid evaporate more….. when it has greater surface area.
A liquid will evaporate more….. when a draught blows over its surface
Answer:
Otherwise, as long as the air is not saturated with water vapor - which is to say that the humidity is below 100% - some evaporation can occur at any temperature when there is liquid water to evaporate. The higher the temperature, the faster evaporation takes place, and the lower the temperature, the slower evaporation takes place.
Which of the following is an example of an endothermic reaction?
A. Respiration
B. Acid neutralization
C. Combustion
D. Photosynthesis
Answer:
D, photosynthesis
Explanation:
Q2.
1.0 kg of ice at -10°C is added to 10 g of water at 0°C.
(a)
Find the final temperature of the mixture. (The specific latent heat of fusion of
ice is 336 J/g and the specific heat capacity of ice is 2000 J kg K-1)
Please help
Answer:
gsbddgshdhsghhdhdhvvs
physics practicle according reduce syllabus
Answer:
yeah which class it's for
B. La velocidad de los electrones en los conductores metálicos es muy pequeña, del orden de algunos mm por segundo. ¿Cómo podrías explicar que cuando se cierra el interruptor de, una bombilla situada a 10m de distancia se ilumina casi instantáneamente? (explica tu respuesta construyendo una hipótesis deductiva a partir de la relación de algunas leyes físicas y teorías científicas.)
Answer:
electromagnetic wave. this energy is what lights the bulb.
Explanation:
When you close an electrical circuit, the electrons have a small drag speed, but the fluctuation of the electric field that is created originates by Lenz's law a magnetic field and the appearance of this magnetic field creates a fluctuating elective field, these two fields together forms a wave called an electromagnetic wave.
This electromagnetic wave has a speed given by the relation
v = √1 /ε μ
in a vacuum this speed is equal to the speed of light, which is worth 3 10⁸ m/s this very high value so the energy transported by this wave can travel the distance of 10 m in less than 10⁻⁷ s, This energy is what lights the bulb.
what is tue cause of upthrust ?
it's caused by a pressure that is large on the button of an object that it is on the top of an object submerged in a liquid.
Explanation:
This is why object appear to weigh less when immersed in a liquid. If the upthrust is greater than the weight of the object, the object will rise up through the liquid.
Total distance between Karachi and Hyderabad is 120 km , if a car speed is 40 km/h, In how many hours it can travel back to Hyderabad
it takes 6 hours to travel back to Hyderabad
( TRUE false )
1.)manuals are the organic matter.
2.)combine is used for sowing the seeds.
3.) the first agricultural task is sowing of seeds.
4.) many plants are first grown in Kinder Gardens and then sown in fields.
5.) earthworm are farmer friendly.
6.)substance that kills
pests are called weedicides.
7.) animals which provide us both egg and flesh are called milch animals.
8.) Grains should be dried in Sun before storage.
9.)wheat,gram,barley,potato, are kharif crops.
10.) the crops on in June /July and harvested in September/ October are called rabi crops.
plz answerzz fast
Answer:
number 6 is wrong
the answer is pesticides
2.combines are used for harvesting or threshing.so number 2 is wrong
at least you tried
Explanation:
there is no such thing as weedicides
Answer:
1. True
2.True
3.False
4. True
5. True
6.False
7.False
8.True
9.False
10.False
kaleidoscope works on the principal of
Answer:
Multiple reflections.Explanation:
Kaleidoscopes work on the principle of multiple reflections.
The mirrors reflect the images of objects inside, creating a symmetrical pattern.
When you look at your reflection in one mirror, you see light that has come from your face and bounced off the mirror.
Find the odd one out a)Planets moving on it's axis,Strings of guitar (being played),Motion of a ferry wheel,The vehicles moving on a straight road. b)Motion of the moon around the earth,Motion of the earth around the sun,Motion of a merry-go-round,Heart-beat in a healthy person. c)Motion of a bullet fired from gun,Motion of a football player in the ground,Motion of a vehicle on a straight road,Motion of an apple falling from a tree
Answer:
a) Strings of guitar (being played)
b) Heart-beat in a healthy person
c) Motion of an apple falling from a tree
Explanation:
a) The motion of the string of a guitar being played is the only motion involving simple harmonic motion.
b) All the other motions are circular motion except the heart beat in a healthy person, which is periodic.
c) The motion of an apply falling from a tree is the only motion under the complete influence of gravity from the onset till the end.
derive an expression for resistivity of conductor of length l and area of cross section A
Answer
Resistivity R = K * L / A where resistivity is constant for material, L the length of the material and A the area of the material
K = R * A / L where R is the resistance of the material
1 point
40 The diagram below shows an electrical circuit made up of a cell and three loads. The
voltage established by the cell and the resistance of each load is marked on the
diagram. Select the current flowing through the 3-ohm load.
www
1 ohm
12V
2 ohms
WWW
3 ohms
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A. 4 amps
B. 2 amps
C. 5 amps
D. 0.25 amps
SPS106 DOK 3
Answer:
Option B. 2 A.
Explanation:
The following data were obtained from the question:
Resistance 1 (R1) = 1 Ω
Resistance 2 (R2) = 2 Ω
Resistance 3 (R3) = 3 Ω
Potential difference (V) = 12 V.
Current through the 3 Ω (I3) =?
Next, we shall determine the total resistance of the circuit.
This can be obtained as follow:
Resistance 1 (R1) = 1 Ω
Resistance 2 (R2) = 2 Ω
Resistance 3 (R3) = 3 Ω
Total resistance (R) =.?
R = R1 + R2 + R3
R = 1 + 2 + 3
R = 6 Ω
Next, we shall determine the current flowing in the circuit.
This can be obtained as follow:
From ohm's law,
Voltage (V) = current (I) x resistance (R)
V = IR
Potential difference (V) = 12 V.
Resistance (R) = 6 Ω
Current (I) =?
V = IR
12 = I x 6
Divide both side by 6
I = 12/6
I = 2 A.
Since the circuit is in series connection, therefore, the same current will flow through each resistor.
Therefore, the current through the the 3 Ω load is 2 A.