Answer:
Recall that the electric potential is defined as the potential energy per unit charge, i.e. V=PEq V = PE q . ... The equation for the electric potential due to a point charge is V=kQr V = kQ r , where k is a constant equal to 9.0×109 N⋅m2/C2.
Explanation:
Alex, parked by the side of an east-west road, is watching car P, which is moving in a westerly direction. Barbara, driving east at a speed 52 km/h, watches the same car. Take the easterly direction as positive. If Alex measures a speed of 78 km/h for car P, what velocity will Barbara measure?
Answer:
[tex]v_{PB} = 130\ km/h[/tex]
Explanation:
Since, Alex is at rest. Therefore, the speed measured by him will be the absolute speed of car P. Therefore, taking easterly direction as positive:
[tex]Absolute\ Velocity\ of\ Car\ P = v_{P} = -78\ km/h[/tex]
And the absolute velocity of Barbara's Car is given as:[tex]Absolute\ Velocity\ of\ Barbara's\ Car = v_{B} = 52\ km/h[/tex]
Now, for the velocity of Car p with respect to the velocity of Barbara's Car can be given s follows:
[tex]Velocity\ of\ Car\ P\ measured\ by\ Barbara = v_{PB} = v_{B}-v_{P}\\\\v_{PB} = 52\ km/h-(-78\ km/h)[/tex]
[tex]v_{PB} = 130\ km/h[/tex]
the question is in a picture
Answer:
same for all objects
Explanation:
earth pulls every object by same force of gravity
Two wave pulses pass each other on a string. The pulse traveling toward the right has positive amplitude, whereas the pulse traveling toward the left has equal amplitude in the negative direction. What happens when they occupy the same region of space at the same time?
a. constructive interference occurs
b. destructive interference occurs.
c. a standing wave is produced.
d. a traveling wave is produced.
e. a wave pulse is produced.
Answer:
destructive interference occurs
Plz help
Fill in the blank with the correct observation from the simulation.
As the days go on, the distance that the moon is from the sun in the night sky
A. Stays the same
B. Decreases
C. Increases
Starting at New Moon, The visual distance increases for about 2 weeks, then decreases for about the next 2weeks, until the next New Moon.
On the average, it changes by about 12° per day.
HELP right awayyy !!!
Answer:
Question 4 is actually Acceleration
Which wave has high enough energy to cause damage to skin and sometimes cancer?
Answer: All UV can have harmful effects on biological matter (such as causing cancers) with the highest energies causing the most damage.
Explanation:
Thomas the Tank Engine (a train) is going 80 m/s and slows down to 30 m/s over a period of 30s. What is his deceleration? Acceleration= (final velocity-initial velocity)/ time A. -1.67 m/s/s B. 0.67 m/s/s C. -50 m/s/s D. 50 m/s/s
Answer: D
Explanation:
en the current in one coil changes at a rate of 3.2 A/s, an emf of 5.7 is induced in a second, nearby coil. What is the magnitude of the mutual inductance of the two coils
Given that,
The rate of change of current = 3.2 A/s
Emf induced in the coil = 5.7 V
To find,
The magnitude of the mutual inductance of the two coils.
Solution,
The mutual inductance between the coils is given by the formula as follows :
[tex]\epsilon=M\dfrac{dI}{dt}\\\\M=\dfrac{\epsilon}{\dfrac{dI}{dt}}\\\\M=\dfrac{5.7}{3.2}\\\\=1.78\ H[/tex]
So, the mutual inductance of the two coils is 1.78 H.
A light wave passes through an aperture (that is, a narrow slit). When it does so, the degree to which the wave spreads out will be...
Explanation:
Single slit diffraction
Diffraction is the phenomenon of spreading out of waves as they pass through an aperture or around objects. Diffraction occurs when the size of the aperture or obstacle is of the same order of magnitude as the wavelength of the incident wave. For very small aperture sizes, the vast majority of the wave is blocked. in case of large apertures the wave passes by or through the obstacle without any significant diffraction.
At 3.00 m from a source that is emitting sound uniformly in all directions, the sound level (b) is 60.0 dB.
How many meters from the source would the sound level be one-fourth the sound level at 3.00 m?
Given that,
At 3.00 m from a source that is emitting sound uniformly in all directions, the sound level is 60.0 dB.
To find,
The distance from the source would the sound level be one-fourth the sound level at 3.00 m.
Solution,
The intensity from a source is inversely proportional to the distance.
Let I₁ = 60 dB, r₁ = 3 m, I₂ = 60/4 = 15 dB, r₂ =?
Using relation :
[tex]\dfrac{I_1}{I_2}=\dfrac{r_2^2}{r_1^2}\\\\r_2^2=\dfrac{I_1r_1^2}{I_2}\\\\r_2^2=\dfrac{60\times (3)^2}{15}\\\\r_2=6\ m[/tex]
So, at a distance of 6 m the sound level will be one fourth of the sound level at 3 m.
Why does a stop sign appear red?
Answer:
because it’s suppose to be red like a stop light.
Explanation:
So it tells you to stop
A 3 kg mass is travelling in a circle of 0.1 m radius with a speed of 2 m/s. What is the centripetal acceleration?
a = v² / R = (2 m/s)² / (0.1 m) = 40 m/s²
Two students (90.0 kg and 60.0 kg) on roller skates face-to-face push against each other. The 90.0 kg student moves at 5.0 m/s just after their hands lose contact. What is the velocity of the other student?
Given that,
Mass of student 1, m₁ = 90 kg
Mass of student 2, m₂ = 60 kg
Speed of student 1, v₁ = 5 m/s
To find,
The velocity of the other student.
Solution,
Using the conservation of momentum to find the velocity of the other student. Let it is v₂.
[tex]m_1v_1=m_2v_2\\\\v_2=\dfrac{m_1v_1}{m_2}\\\\v_2=\dfrac{90\times 5}{60}\\\\=7.5\ m/s[/tex]
So, the velocity of the other student is 7.5 m/s.
. Emily pushes a 38.8 kg grocery cart of groceries by exerting a 76.0 N force on the handle inclined at 40.0 degrees below the horizontal. What are:
a. The horizontal and vertical components of Emily’s force
b. The acceleration of the cart?
Answer:
a) [tex]F_{x} = 58.2 N[/tex]
[tex] F_{y} = 48.9 N [/tex]
b) a = 1.5 m/s²
Explanation:
a) The horizontal and vertical components of Emily's force can be found knowing the angle and the exerted force.
Since the handle is inclined at 40.0° below the horizontal we have:
[tex] F_{x} = |F|*cos(\theta) = 76.0 N*cos(40) = 58.2 N [/tex]
[tex] F_{y} = |F|*sin(\theta) = 76.0 N*sin(40) = 48.9 N [/tex]
b) The acceleration of the car can be calculated as follows:
[tex] F_{x} = ma [/tex]
We used the horizontal component of the force because the cart is moving in that direction.
[tex] a = \frac{F_{x}}{m} = \frac{58.2 N}{38.8 kg} = 1.5 m/s^{2} [/tex]
Hence, the acceleration of the car is 1.5 m/s².
I hope it helps you!
A student adds two vectors of magnitudes 48 m and 22 m. What are the maximum and minimum possible values for the resultant of these two vectors.
Answer:
Maximum=70 m
Minimum=26 m
Explanation:
Vector Addition
Since vectors have magnitude and direction, adding them takes into consideration not only the magnitudes but also their respective directions. Two vectors can be totally collaborative, i.e., point to the same direction, or be totally opposite. In the first case, the magnitude of the sum is at maximum. Otherwise, it's at a minimum.
Thus, the maximum magnitude of the sum is 48+22 = 70 m and the minimum magnitude of the sum is 48-22= 26 m
Energy stored because of an object's height above the Earth's surface is_____energy.
nuclear
gravitational
electrical or chemical
A person holds a ladder horizontally at its center. Treating the ladder as a uniform rod of length 4.15 m and mass 7.98 kg, find the torque the person must exert on the ladder to give it an angular acceleration of 0.396 rad/s2.
Answer:
4.535 N.m
Explanation:
To solve this question, we're going to use the formula for moment of inertia
I = mL²/12
Where
I = moment of inertia
m = mass of the ladder, 7.98 kg
L = length of the ladder, 4.15 m
On solving we have
I = 7.98 * (4.15)² / 12
I = (7.98 * 17.2225) / 12
I = 137.44 / 12
I = 11.45 kg·m²
That is the moment of inertia about the center.
Using this moment of inertia, we multiply it by the angular acceleration to get the needed torque. So that
τ = 11.453 kg·m² * 0.395 rad/s²
τ = 4.535 N·m
The Torque will be "4.535 N.m".
Given:
Mass of ladder,
m = 7.98 kgLength of ladder,
L = 4.15 m
The moment of inertia will be:
→ [tex]I = \frac{mL^2}{12}[/tex]
[tex]= \frac{7.98\times (4.15)^2}{12}[/tex]
[tex]= \frac{7.98\times 17.2225}{12}[/tex]
[tex]= 11.45 \ kg.m^2[/tex]
hence,
The torque will be:
→ [tex]\tau = 11.453\times 0.395[/tex]
[tex]= 4.535 \ N/m[/tex]
Thus the above approach is correct.
Learn more about torque here:
https://brainly.com/question/19247046
If 65 kW is to be transmitted over two 0.100 ohm lines, estimate how much power is saved if the voltage is stepped up from 120 V to 1200 V
Answer: 5.91kw
Explanation:
given data:
power = 65kw
voltage stepped up = 120v t0 1200
R 0.100
Solution:
when the it is stepped to 120v
[tex]P = VI \\65000/ 120I\\ I = 541.7A\\[/tex]
power loss
[tex](I^{2} )R*2\\= (541.7^{2})0.100*2\\= 58536.2w[/tex]
when it is stepped to 1200v
[tex]\frac{65000}{1200} \\ I = 54.17A\[/tex]
[tex](I^{2} )R*2\\= (54.17^{2})0.100*2\\= 586.9w[/tex]
total power saved
[tex]= 65kw - 58.5kw - 0.59kw\\= 5.91kw[/tex]
if a certain car, going with speed v1, rounds a level curve with a radius r1, it is just on the verge of skidding. if its speed is now doubled, the radius of the tightest curve on the same road that it can round without skidding is:
Answer:
The correct answer is 4R1
Explanation:
According to the given scenario ,the radius of the tightest curve on the same road without skidding is as follows:
As we know that
Centeripetal Acceleration is
= v^2 ÷ r
In the case when velocity becomes 2 times so the r would be 4 times
So, the radius of the tightest curve on the same road without skidding is 4R1
are aliens real in 2020
Answer:
i believe that they are or there's something out there
Explanation:
:)
A particular engine has a power output of 5 kW and an efficiency of 30%. If the engine expels 6464 J of thermal energy in each cycle, find the heat absorbed in each cycle. Answer in units of J.
Answer:
The heat absorbed in each cycle is 9,234.286 J
Explanation:
Given;
power output, P = 5 kW = 5,000 W
efficiency of the engine, e = 30 % = 0.3
thermal heat expelled, [tex]Q_c[/tex] = 6464 J
let the heat absorbed = [tex]Q_h[/tex]
The efficiency of the engine is given as;
[tex]e = \frac{W}{Q_h} = \frac{Q_h-Q_c}{Q_h} = \frac{Q_h}{Q_h} - \frac{Q_c}{Q_h} = 1-\frac{Q_c}{Q_h}\\\\e = 1-\frac{Q_c}{Q_h}\\\\0.3 = 1-\frac{Q_c}{Q_h}\\\\\frac{Q_c}{Q_h} = 1-0.3\\\\\frac{Q_c}{Q_h} = 0.7\\\\Q_h = \frac{Q_c}{0.7} \\\\Q_h = \frac{6464}{0.7} = 9,234.286 \ J.[/tex]
Therefore, the heat absorbed in each cycle is 9,234.286 J.
The scientific method can easily be misinterpreted as ___________. Question 1 options: a great magical trick, or slide of hands, rather than factual an "auto mechanics" guide to Science Investigation a "cookbook" recipe for performing scientific investigations the perfect method for finding the answers to all questions
Answer:
I think the answer is
a "cookbook" recipe for performing scientific investigations
Explanation:
The physical quantity which have both magnitude and direction is a vector?why?
Answer:
hiiiiiiiiiiiii baby.........
What is the period of an object that makes 6 revolutions a minute?
Answer:
T = 10 s
Explanation:
First, we need to find the frequency of the object as follows:
[tex]Frequency = f = \frac{Speed\ in\ rpm}{60}[/tex]
where,
Speed = Angular Speed = 6 rpm
Therefore,
[tex]f = \frac{6\ rpm}{60}\\\\f = 0.1\ Hz[/tex]
Now, for time period (T):
[tex]Time\ Period = T = \frac{1}{f}\\\\T = \frac{1}{0.1\ Hz}\\\\[/tex]
T = 10 s
what is the main cause of seafloor spreading?
Answer:
As tectonic plates slowly move away from each other, heat from the mantle's convection currents makes the crust more plastic and less dense.
Explanation:
Answer: The main cause of sea floor spreading are the directions and force of the moving tectonic plates.
Explanation:
Conveyor belts are often used to move packages around warehouses. The conveyor shown below moves packages at a steady 4.0 m/s. A 500 N employee decides to catch a ride by sitting on a 1,000 N box for a 50 m trip as shown below:
What is the work done by the employee on the box?
Answer:
0 j
Explanation:
The work done by the employee on the box at the given zero displacement is 0 J.
The given parameters;
Constant velocity of the conveyor, v = 4 m/sWeight of the employee, W = 500 NWeight of the box, W = 1,000 NDistance of the trip, h = 50 mThe work done by the employee on the box is calculated as follows;
W = Fd
where;
F is the applied force on the box by employee = weight of the employeed is the distance through which the box is movedSince the employee sits on the box without moving it, the distance moved by the box = 0
W = 500 x 0
W = 0 J
Thus, the work done by the employee on the box is 0 J.
Learn more about work done and displacement here: https://brainly.com/question/8635561
An image is a copy of an objecí formed by what light
Answer:
Plane mirror
Explanation:
A virtual image is a copy of an object formed at the location from which the light rays appear to come.
Is electricity matter?
EXPLAIN.
Answer:
Yes it is matter
Explanation:
In physics, usually the word "electricity" isn't really used. "Electric current" is more common, and is defined as the flow of charges, where the charges are held by particles (electrons). Electrons have mass, so they are definitely matter.
What causes the magnetic field around the wire?
Magnetic field
O A. An electric current
O B. An electric field
PREVIOUS
An electric current causes the magnetic field around the wire. The correct answer is A.
The magnetic field around a wire is caused by the flow of electric current through the wire. When an electric current passes through a wire, it generates a magnetic field that forms circular lines of magnetic flux around the wire. This phenomenon is described by Ampere's law, which states that a magnetic field is produced by an electric current and its strength is directly proportional to the magnitude of the current.
The relationship between the electric current and the magnetic field can be understood using the right-hand rule. If you wrap your right hand around the wire with your thumb pointing in the direction of the current, the curled fingers indicate the direction of the magnetic field lines.
Therefore, an electric field is generated by an electric charge, not by an electric current. While an electric field can exist around a wire if there is a potential difference (voltage) applied across it, it is the flow of electric current that primarily generates the magnetic field.
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A water-skier of mass 75.0 kg initially at rest is being pulled due east by a horizontal towrope. The rope exerts a force of 365 N (east). The water (and air) exerts a combined average frictional force of 190 N (in the opposite direction). How fast will the skier be moving after a distance of 38.0 m?
Answer:
The skier will be moving at 13.31 m/s.
Explanation:
To calculate the velocity of the skier we need to find the acceleration, as follows:
[tex] \Sigma F = ma [/tex]
[tex] F_{r} - F_{f} = ma [/tex]
Where:
[tex] F_{r}[/tex]: is the force due to the rope = 365 N
[tex] F_{f}[/tex]: is the combined average frictional force = 190 N
m: is the mass = 75.0 kg
[tex] a = \frac{365 N - 190 N}{75.0 kg} = 2.33 m/s^{2} [/tex]
Now, we can calculate the velocity of the skier by using the following kinematic equation:
[tex] v_{f}^{2} = v_{0}^{2} + 2ad [/tex]
Where:
[tex] v_{f}[/tex]: is the final velocity =?
[tex] v_{0}[/tex]: is the initial velocity = 0 (the skier is initially at rest)
d: is the distance = 38.0 m
[tex] v_{f} = \sqrt{2*2.33 m/s^{2}*38.0 m} = 13.31 m/s [/tex]
Therefore, the skier will be moving at 13.31 m/s.
I hope it helps you!