Answer:
First
Explanation:
i took the test and its first
A 700 kg car going 12 m/s speeds up to 30.6 m/s in 7 seconds. How much work was done to increase its speed?
Answer:
Approximately [tex]2.8 \times 10^{5} \; \rm J[/tex] (assuming that the car is moving on level ground, and that there is no friction to hinder the motion of the car.)
Explanation:
Formula for the kinetic energy, [tex]\rm KE[/tex], of an object of [tex]m[/tex] travelling at velocity [tex]v[/tex]:
[tex]\displaystyle \text{KE} = \frac{1}{2}\, m \cdot v^{2}[/tex].
Let [tex]v_1[/tex] and [tex]v_2[/tex] denote the velocity of this car before and after the acceleration.
Kinetic energy of this car before the acceleration:
[tex]\begin{aligned}\text{KE}_1 &= \frac{1}{2}\, m \cdot {v_1}^{2} \\ &= \frac{1}{2} \times 700\; \rm kg \times (12\; \rm m \cdot s^{-1})^{2} \\ &\approx 5.0 \times 10^{4}\; \rm J\end{aligned}[/tex].
Kinetic energy of this car after the acceleration:
[tex]\begin{aligned}\text{KE}_2 &= \frac{1}{2}\, m \cdot {v_2}^{2} \\ &= \frac{1}{2} \times 700\; \rm kg \times (30.6\; \rm m \cdot s^{-1})^{2} \\ &\approx 3.3\times 10^{6}\; \rm J\end{aligned}[/tex].
Assume that this car was travelling on level ground. Also assume that there is no friction to hinder the motion of this car. The work of the engine of this car would be equal to the amount of [tex]\rm KE[/tex] that the car has gained:
[tex]\rm KE_2 - KE_1 \approx 2.8\times 10^{5}\; \rm J[/tex].
which vector is the sum of vectors a and b
Answer:
C
Explanation:
Vector A points up
Vector B points right
The combination must be both up and right which is C
In a clear cup there are three substances. Their densities are 3, 1, and 2. From top of the cup to the bottom, what would the order of substances be sitting inside the cup?
Answer:
1, 2 and 3
Explanation:
The most dense substance will settle at the bottom of the cup
4. Anaerobic exercise helps type 2 diabetes.
a. True
b. False
Answer:
true
Explanation:
b/c anaerobic exercis helps type 2 diabetes
Describe the three methods of thermal energy transfer and provide a sketch that depicts each:
Conduction:
Convection:
Radiation:
Answer:
a)the process by which heat or electricity is directly transmitted through the material of a substance when there is a difference of temperature
b)the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat
c)radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
What force is caused by tiny collisions, called microwelds, on surfaces that
are stuck together?
A. heat
B. energy
C. air resistance
D. friction
Answer:
D. Friction
Explanation:
"Friction is caused by microwelds that form between two surfaces. Microwelds are stronger when the two surfaces are pushed together with a greater force." - ( Module 3 • Forces and Newton’s Laws) quoted
hope this helps and is right. p.s. i really need brainliest :)
Answer:
Friction
Explanation:
Took The Test
What provides evidence that has helped earth scientists determine the age of the earth more precisely?
radioactive dating
atmospheric pressure
helium dating
earth’s distance from the moon
Answer:
the answer is radioactive dating
When ___ attacks the surface of a metal, it becomes tarnished.
Answer:corrosion (i believe)
Explanation:
Answer
Mix baking soda and salt with hot water and cover everything with it. The proportions are not crucial, but about 1 tablespoon of salt and 1 tablespoon of baking soda to 3 dl water should do the trick. Lightly tarnished objects should clean up in a few minutes, and you just rinse them of and dry them.
Explanation:
After the full moon, the moon begins its shrinking or_phases. During these phases, the light side of the moon is on the_
A. Waning, left
B. Waxing, right
C. Waxing, left
D. Waning, right
A bat produces a sound at 17,250Hz and wavelength 0.019m. What is
the speed of the sound?
Explanation:
v = f × /\
v = 17250 × 0.019
v = 327.75ms²
A produces a sound at a frequency of 17,250 Hz and wavelength of 0.079 m then the speed of sound will be equal to 327.75 m/s².
What is Wavelength?The distance between two identical locations (adjacent crests) in successive cycles is known as the wavelength, and it is used to describe waveform signals that are transmitted over wires or into space. Typically, in wireless systems, this length is specified in meters (m), centimeters (cm), or millimeters (mm). The wavelength is more frequently described in nanometers (nm), which are units of 10⁻⁹ m, or angstroms, which are units of 10⁻¹⁰ m, for infrared (IR), visible light (UV), and gamma radiation.
As per the given information in the question,
Frequency, f = 17,250 Hz
The wavelength λ = 0.019 m
Then the speed of the sound (v) will be,
v = f × λ
v = 17250 × 0.019
v = 327.75 m/s²
To know more about Wavelength:
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PWEESE HELPPPP I'LL GIVE BRAINLIEST, (NO LINKS OR I'LL REPORT)
(︶^︶)
A sound wave is made of a series of compressions and
a.
extensions.
c.
rarefactions.
b.
volumes.
d.
refractions.
Answer:
extensions.
Explanation:
Hope this helps
Answer:
extensions i think because sound waves travel through the air and to our ears so its extended
Explanation:
GIVING BRAINLIEST PLEASE HELP!!
-if you answer correctly ill give you brainliest which will give you 20pts-
Answer:
B
Explanation:
inside of a balloon is gas so it has room to move freely
which statement identifies a reason to preserves wetlands
Answer:
They store floodwater
Explanation:
A 905 kg test car travels around a 3.25 km circular track. if the magnitude of the force that maintains the car's circular motion is 2140 N, what is the car's tangential speed?
Choose the correct answer?
Answer:
B
Explanation:
How would an object’s kinetic energy change if it’s mass decreased by a factor of 3 and it moved 6 times faster?
Answer: Decreases in mass cause decreases in kinetic energy due to the aforementioned positive relationship between the two. Therefore when mass is decreased, an increase in kinetic energy is possible if velocity increases.
Answer:: Decreases in mass cause decreases in kinetic energy due to the aforementioned positive relationship between the two.
john and kate live in the regions marked on the map. john experiences severe winters, with snowstorms and blizzards. in contrast, kate hardly ever experiences temperatures near or below freezing. which of the following statements explain the climate differences in these locations??
Answer:
A. Kate’s location is at a lower latitude.
C. Kate’s location absorbs sunlight that travels a shorter distance through the atmosphere.
Explanation:
^
Answer:
edmentum :-))
Explanation:
How many degrees equal π in radians? How many revolutions (turns) equal π radians?
Answer:
It follows that the magnitude in radians of one complete revolution (360 degrees) is the length of the entire circumference divided by the radius, or 2πr / r, or 2π. Thus 2π radians is equal to 360 degrees, meaning that one radian is equal to 180/π ≈ 57.295779513082320876 degrees.
Explanation:
How will a ray of light traveling parallel to the principle axis of a concave mirror be reflected back
Answer:
It will be reflected to the principal focus of the concave mirror
Explanation:
This is because all rays parallel and close to the principal axis of a concave mirror get reflected to the principal focus of the mirror.
For a ray to be parallel to the mirror, it must be coming from an infinite distance.
So, using the mirror formula,
1/u + 1/v = 1/f where u = object distance from mirror, v =image distance form mirror and f =focal length of mirror.
Since u = infinite distance = ∞
1/u + 1/v = 1/f
1/∞ + 1/v = 1/f
0 + 1/v = 1/f
1/v = 1/f
v = f
So, the image is at the principal focus.
So, the ray of light parallel to the principal axis of the concave mirror is reflected to the principal focus of the concave mirror.
to transmit heat sound or electricity through a medium
Answer:Electrical conduction is the transfer of electrically charged particles through a medium, such as electricity traveling through the power lines in your house. Sound conduction (or acoustic conduction) is the transfer of sound waves through a medium, such as vibrations from loud music passing through a wall.
Explanation: Trust
in prokaryotic and eukaryotic cells the amount of water in the cell is kept at a steady state. The organelles
through which water passes into and out of cell is the
A) cell membrane
B) cell wall
C) nuclear
D) ribosome
Answer:
A
Explanation:
It would not be C because prokaryotic cells don't have a nucleus. And if you're looking for a body in the cell that controls the nutrients and water it would be A.
A metal sphere of radius 10 cm carries a charge of 2.0 MicroCoulomb.What is the magnitude of the electric field 5.0 cm from the sphere's surface?
Answer:
E = 7200 J = 7.2 KJ
Explanation:
The electric field due to a sphere is similar to the electric field due to a point charge. It is calculated by the use of the following formula:
[tex]E = \frac{kq}{r^2}\\[/tex]
where,
E = Electric Field = ?
k = Coulomb Constant = 9 x 10⁹ Nm²/C²
q = charge on sphere = 2 μC = 2 x 10⁻⁶ C
r = distance from the center of the sphere to the location = 5 cm = 0.05 m
Therefore,
[tex]E = \frac{(9\ x\ 10^9\ Nm^2/C^2)(2\ x\ 10^{-6}\ C)}{(0.05\ m)^2}[/tex]
E = 7200 J = 7.2 KJ
The properties of metals depend mainly on the number and arrangement of neutrons
True
False
Answer:
False
Explanation:
Electrons
5. What is the frequency of a sound wave when the speed of the sound is 340 m/s and has a wavelength of 1.21 m?
Explanation:
v = f × /\
340 = 1.21f
f = 280.99Hz
An object is in motion if ___
Answer:
An object is in notion if its position change with time.
The small piston of a hydraulic lift has an area of 0.20 m2. A car weighing 1200 N sits on a rack mounted on the large piston. The large piston has an area of 0.90 m2. What is the mechanical advantage of the hydraulic lift?
Answer:
4.5
Explanation:
Given the following
Weight of the car = 1200N (Load)
Let us get the effort by using the formula;
F1/A1 = F2/A2
Substitute the given values
1200/0.9 = F2/0.2
Cross multiply
0.9F2 = 1200 * 0.2
0.9F2 = 240
F2 = 240/0.9
F2 = 266.67N
Hence the effort is 266.67N
Mechanical Advntage = Load/Effort
MA = 1200/266.67
MA = 4.5
Hence he mechanical advantage of the hydraulic lift is 4.5
Someone please help me figure this out
Answer:
the answer is A
Explanation:
hope this helps you will u plz mark me sa brainliest?
14. A light bulb has a resistance of 8 ohms and a maximum current of 10 A How much voltage can
be applied before the bulb will break?
Answer:
80 volts.
Explanation:
From the question,
Applying Ohm's law
V = IR...................... Equation 1
Where V = Voltage, I = maximum current of the bulb, R = Resistance of the bulb.
Given: I = 10 A, R = ohms
Substitute these values into equation 1
V = 10×8
V = 80 volt.
Hence the voltage that can be applied is 80 volt.
This diagram shows a heating curve for water.
At which segment does freezing occur?
The answer is B.) W-V
Hope this helps
Answer:
it is B
Explanation:
Because I agree with her and also got 100
A hiking trail is 150 meters long. A mountain lion can run the entire trail in 30 seconds.
How fast does the mountain lion run?
Answer:
5 meters per second
explanation
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