What is the mass of mars
the mass of mars is
6.39 × 10^23 kg
Find the center of mass of a one-meter long rod, made of 50 cm of iron (density 8gcm3) and 50 cm of aluminum (density 2.7gcm3).
The center of the mass of a one-meter long rod, made of 50 cm of iron (density 8gcm3) and 50 cm of aluminum (density 2.7gcm3) is 37.62(cm)
Calculations and Parametersλ Fe =8g/cm,λ Al =2.7g/cm
There is a metal rod 1 meter long, with the first 50cm being iron and the other 50cm aluminum. the problem is solved in a one-dimensional case meaning it's a thin rod.
Next, we would solve by definition of the center of mass
We would also note that the masses of iron and aluminum are just the product of their length and linear density.
[tex]X_C_M[/tex]= [tex]\frac{8(g/cm). \frac{2500(cm^2)}{2} + 2.7 (g/cm). \frac{7500(cm^2)}{2} }{8(g/cm).50(cm) + 2.7(g/cm). 50 (cm)}[/tex]
= 37.62(cm)
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In an attempt to escape his island, Gilligan builds a raft and sets to sea. The wind shifts a great deal during the day, and he is blown along the following straight lines:
2.5 km 45° north of west; then
4.70 km 60° south of east; then
5.1 km straight east; then
7.2 km 55° south of west; and finally
2.8 km 5° north of east.
What is his final position relative to the island?
km
° south of east
The final position of Gilligan in kilometers and degrees south of east relative to the island is 9.07 km, 61.4° south of east.
What is a vector simple ?A vector is a quantity or phenomenon that has two independent properties: magnitude and direction.
The term also denotes the mathematical or geometrical representation of such a quantity.
According to the question,
Suppose, the direction east as i, direction west as -i, direction north as j and direction south as j.
Therefore,
1. : 2.5 km 45° north of west
[tex]= 2.5 cos45 (-i) + 2.5 cos45 (j)\\ = -1.77(i) + 1.77(j)[/tex]
2. : 4.7 km 60° south of east
[tex]= 4.7 cos60 (i) + 4.7 sin60 (-j) \\= 2.35(i) - 4.07(j)[/tex]
3. : 5.1 km straight east
[tex]=5.1(i)[/tex]
4 : 7.2 km 55° south of west
[tex]= 7.2 cos55 (-i) + 7.2 sin55 (-j)\\ = -4.13(i) - 5.9(j)[/tex]
5: 2.8 km 5° north of east
[tex]= 2.8 cos5 (i) + 2.8 sin5 (j)\\= 2.79(i) + 0.24(j)[/tex]
The sum of all the above yields,
[tex]R = 4.34(i) + 7.96(-j)[/tex]
The magnitude of the resultant is:
[tex]|R| =\sqrt{4.34^{2} + (-7.96)^{2} }= 9.07[/tex]
The angle that the resultant makes is as follows.
θ= [tex]tan^-^1(\frac{7.96}{4.34} )\\[/tex]
θ = 61.4°
Hence,
Final position relative to the island is 9.07 km, 61.4° south of east.
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Neil Armstrong dropped a hammer on the moon. If it took 4 seconds to fall and the final speed was 8 m/s, what is the acceleration due to gravity on the moon?
Answer:
2
Explanation:
8-0/4
Final velocity-initial velocity/time taken
a man carries a hand bag by hanging on his hand and moves horizontally where the bag does not move up or down. What is the work done on the bag? The man gets tired after sometime of the movement. Why?
The work done by the man is the product of his applied force and the displacement of the bag and the man gets tired because his internal energy has be converted to work.
What is work done by the man?The work done by the man is the product of his applied force and the displacement of the bag.
Why the man gets tiredThe man gets tired because his internal energy has be used to do work on the bag.
Thus, the work done by the man is the product of his applied force and the displacement of the bag and the man gets tired because his internal energy has be converted to work.
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Hi! Whoever can answer this question the best I will give the brainliest answer!!
Describe the structure of a battery and how it works.
Thank you!! ✨
What is inertia?by Walter Levin..
Inertia is directly proportional to mass.
What is Walter Lewin famous for?
Walter Hendrik Gustav Lewin (born January 29, 1936) is a Dutch astrophysicist and former professor of physics at the Massachusetts Institute of Technology.
Lewin earned his doctorate in nuclear physics in 1965 at the Delft University of Technology and was a member of MIT's physics faculty for 43 years beginning in 1966 until his retirement in 2009.
According to Walter Levin,
The concept of moment of inertia is demonstrated by rolling a series of cylinders down an inclined plane.
Inertia is the resistance of any physical object to a change in its velocity. This includes changes to the object's speed, or direction of motion. An aspect of this property is the tendency of objects to keep moving in a straight line at a constant speed when no forces act upon them.
By rolling a series of cylinders down on an inclined plane , he demonstrated that a cylinder have a smooth friction.
He compares the rolling cylinder by using hollow cylinder and a heavy cylinder , and finalize the result that a hollow cylinder moves slowly but the heavy cylinder move faster.
Hence , By doing this experiment he explained about the inertia that Inertia depend on the mass of the object. As the heavy the object it will take more time to travel or move.
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Under normal conditions the human heart converts about 13.0 J of chemical energy per second into 1.30 W of mechanical power as it pumps blood throughout the body. (a) Determine the number of Calories required to power the heart for one day
The energy (in calories) required to power the heart for one day is 268.32 Cal
How to convert 1 day to seconds1 day = 24 h
24 h = 24 × 60 = 1440 mins
1440 mins = 1440 × 60 = 86400 s
Thus,
1 day = 86400 s
How to determine the energy (in calories) for 1 day (86400 s)From the question given,
1 s = 13 J
Therefore,
86400 s = 86400 × 13
86400 s = 1123200 J
Divide by 4186 to express in calories
86400 s = 1123200 / 4186
86400 s = 268.32 Cal
Thus, the energy needed to power the heart for 1 day is 268.32 Cal
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Complete question
Under normal conditions the human heart converts about 13.0 J of chemical energy per second into 1.30 W of mechanical power as it pumps blood throughout the body. (a) Determine the number of Calories required to power the heart for one day given that 1 Calorie equals 4186
A cart is being pulled slowed down by a hanging mass. What is the value of the change in its kinetic energy, ΔEk?
Positive
Zero
Negative
Due a decrease in the velocity of the cart, the change in kinetic energy is negative
What is kinetic energy?Kinetic energy is the energy of a body due to its motion.
The change in kinetic energy is positive if the mass of a body or the velocity of the body increases.The change in kinetic energy is negative if the mass of a body or the velocity of the body decreases.The change in kinetic energy is zero if the mass of a body or the velocity of the body remains constant.Since the cart is slowed down, its velocity decreases and the change in kinetic energy is negative.
In conclusion, the change in kinetic energy of a body is affected by the mass and velocity of the body.
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A roller coaster has a mass of 450 kgIt sits at the top of a hill with height 49 m. If it drops from this hill, how fast is it going when it reaches the bottom? Assume there is no air resistance or friction.)
The speed of the roller coater at the bottom of the hill is 31 m/s.
Speed of the roller coater at the bottom of the hill
Apply the principle of conservation of mechanical energy as follows;
K.E(bottom) = P.E(top)
¹/₂mv² = mgh
v² = 2gh
v = √2gh
where;
v is the speed of the coater at bottom hillh is the height of the hillg is acceleration due to gravityv = √(2 x 9.8 x 49)
v = 31 m/s
Thus, the speed of the roller coater at the bottom of the hill is 31 m/s.
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A ball is rolling across the floor at a constant velocity. What is the value of the change in its kinetic energy, ΔEk?
Positive
Zero
Negative
B. When the ball is rolling across the floor at a constant velocity, the change in its kinetic energy is zero.
What is change in kinetic energy?
The change in kinetic energy of an object is the dereference between the final kinetic energy and the initial kinetic energy.
ΔK.E = K.Ef - K.Ei
ΔK.E = 0.5m(vf² - vi²)
where;
K.Ef is the final kinetic energyK.Ei is the initial kinetic energyvf is final velocityvi is initial velocityAt constant velocity, the initial velocity and final velocity are equal.
ΔK.E = 0.5m(0) = 0
Thus, when the ball is rolling across the floor at a constant velocity, the change in its kinetic energy is zero.
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If the current in a wire increases from 5A to 10A, what happens to its magnetic field?
If the current in a wire increases from 5A to 10A, the magnetic field generated will also be doubled.
IntroductionHi ! I will help you to discuss about "magnetic field around a conducting wire". A conducting wire that carried electric current can generate amount of magnetic fields. In a standard winding condition, the increase number of electric current will be proportional to the increase number of the generated magnetic field. In other condition, the increase in distance (between center of field with a point) will be inversly proportional to the increase in the generated magnetic field. So, the magnetic field that generated around a current-carrying wire can be expressed in the following equation.
[tex] \boxed{\sf{\bold{B = \frac{\mu_0 \cdot I}{2\pi \cdot d}}}}[/tex]
With the following condition:
B = perceived magnetic field at a point (Wb/m² or T)[tex]\sf{\mu_0}[/tex] = vacuum permeability = [tex]\sf{4\pi \times 10^{-7} \: Wb/A.m}[/tex] I = electric current (A)d = distance of a point from the wire (m)Problem SolvingWe can assume that:
Only the increase in current affects the change in the value of the magnetic field.Other provisions such as the distance of the point from the conducting wire is considered the same.We know that :
[tex]\sf{I_1 : I_2}[/tex] = 5 : 10 = 1 : 2 >> the ratio between the current flowing in first and second sample.[tex]\sf{d_1 : d_2}[/tex] = 1 : 1What was asked ?
B = perceived magnetic field at a point = ... : ...Step by step :
[tex] \sf{B_1 : B_2} [/tex]
[tex] \sf{\frac{\cancel{\mu_0} \cdot I_1}{\cancel{2\pi} \cdot d_1} : \frac{\cancel{\mu_0} \cdot I_2}{\cancel{2\pi} \cdot d_2}} [/tex]
[tex] \sf{\frac{I_1}{d_1} : \frac{I_2}{d_2}} [/tex]
[tex] \sf{\frac{I_1}{\cancel d} : \frac{I_2}{\cancel d}} [/tex]
[tex] \sf{I_1 : I_2} [/tex]
[tex] \boxed{\sf{\bold{1 : 2}}} [/tex]
ConclusionFrom the above comparison, we can see that the ratio of the magnetic field at a point will be the same as the ratio of the current flowing through the conducting wire is 1 : 2. So, The magnetic field generated will also be doubled.
A thin flexible gold chain of uniform linear density has a mass of 17.1 g. It hangs between two 30.0 cm long vertical sticks (vertical axes) which are a distance of 30.0 cm apart horizontally (x-axis), as shown in the figure below which is drawn to scale.
Evaluate the magnitude of the force on the left hand pole.
The magnitude of the force on the left-hand pole is mathematically given as
f'=0.167N
Q=45 degrees
What is the magnitude of the force on the left-hand pole.?Generally, the equation for Force is mathematically given as
[tex]\frac{mg}{sin \theta}[/tex]
Therefore
[tex]F=\frac{17.1*10^{-3}*9.8}{sin45}[/tex]
F=0.237N
Considering horizontal axis or plane
f'-fcos=0
Therefore
f'=0.237*cos45
f'=0.167N
In conclusion, the slope
[tex]tan\theta= 30/30\\\\tan\theta=1\\\\\theta=45[/tex]
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PLS HELP:
Find the magnitude of an electric field located 7.00 cm from a source charge of - 11 nC. (1nC = 1 x 10-9 C). Will the field lines point toward or away from the source charge? Show your work and include an electric field diagram assuming the source is a point charge
Answer:
E=kQ/r*2
=(9. 10*9)(11.10*-9)/(0,07)*2
=20204 N. C*-1
The field lines will point towards the source charge because it is negatively charged.
A space probe sent to Mars has a weight of 10,000 N on Earth (g = 10). What is its mass?
Answer:
[tex]1,\!000\; {\rm kg}[/tex].
Explanation:
The "[tex]g[/tex]" given in the question likely refers to the strength of the gravitational field. The standard unit of [tex]g[/tex] is [tex]{\rm m \cdot s^{-2}}[/tex], same as the standard unit of acceleration. However, since [tex]1\; {\rm N} = 1\; {\rm kg \cdot m \cdot s^{-2}[/tex], the standard unit of [tex]g[/tex] is equivalent to [tex]{\rm N \cdot kg^{-1}}[/tex].
For instance, the gravitational strength on the surface of the earth is approximately [tex]g = 10\; {\rm N \cdot kg^{-1}}[/tex]. However, the question did not specify the unit of this value.
If the mass of an object is [tex]m[/tex], the weight of that object would be [tex](\text{weight}) = m\, g[/tex] when the gravitational field strength around that object is [tex]g[/tex]. It is given that for the object in this question, [tex]m\, g = (\text{weight}) = 10,\!000\; {\rm N}[/tex] when [tex]g = 10\; {\rm N \cdot kg^{-1}}[/tex]. Therefore, the mass [tex]m\![/tex] of this object would be:
[tex]\begin{aligned}m &= \frac{(\text{weight})}{g} \\ &= \frac{10,\!000\; {\rm N}}{10\; {\rm N \cdot kg^{-1}}} \\ &= 1,\! 000\; {\rm kg}\end{aligned}[/tex].
Hellowww..... =)
What is atomic number ?..
Answer:
The atomic number is the number of protons in an element
So, RCF, or relative centrifugal force should be equal to RCF = [tex]11,18*r*(RPM/1000)^2[/tex]
The radius is measured in centimeters and RPM is revolutions per minute.
What I don't know is, if I plug all the data in the formula, will the result equal to acceleration in meters per second squared, or it will be measured in g's so that if I multiply the g's by 9.8 meters per second square, it will give me the actual acceleration.
After plugging all the data into the equation, the result of the relative centrifugal force (RCF) is measured in terms of g.
What is relative centrifugal force?The relative centrifugal force (RCF) or the g force is the radial force generated by the spinning rotor as expressed relative to the earth's gravitational force.
RCF = ac/g
where;
ac is centripetal accelerationg is acceleration due to gravity[tex]RCF = \frac{\omega ^2 r}{g} = 1.118\times 10^{-5} \ (RPM)^2 r = 11.18r\ (RPM/1000)^2[/tex]
where;
r is radius in cmFor example,Find the maximum RCF of the JS-4.2 rotor can be obtained from its maximum speed (4200 rpm) and its rmax (250 mm);
[tex]RCF = 11.18 \times 25\ cm \times (\frac{4200 \ RPM}{1000} )^2 = 4,930.3 \times g[/tex]
Thus, after plugging all the data into the equation, the result is measured in terms of g.
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A frog leaps from flat ground at 6.32 m/s
at a 36.3 angle. What maximum height
does it reach?
(Unit = m)
Answer:
.714 m
Explanation:
The VERTICAL component is all we are interested in for this Q
Vertical velocity = 6.32 m/s sin 36.3° = 3.742 m/s
Vertical displacement = vo t - 1/2 at^2
= -1/2 at^2 + vo t
max occurs at - b/2a = -3.742/ (2(-1/2(9.81)) = .3814 sec
then vot-1/2 at^2 =
3.742 (.3814) - 1/2 ( 9.81)(.3814^2) = .714 m
Answer:
.714
Explanation:
when 82.5 calories of heat are given to a metallic rod of mass 150g its temperature raises from 20 degree celcius to 25 degree Celsius. what is the specific heat of the metal.
A 150-g metallic rod with a specific heat of 0.11 cal/g.°C absorbs 82.5 calories of heat and its temperature increases from 20 °C to 25 °C.
What is specific heat?It is the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
A metallic rod of mass 150 g (m) absorbs 82.5 cal of heat (Q) and its temperature raises from 20 °C to 25 °C. We can calculate the specific heat (c) of the metal using the following expression.
Q = c × m × ΔT
c = Q / m × ΔT
c = 82.5 cal / 150 g × (25 °C - 20 °C) = 0.11 cal/g.°C
A 150-g metallic rod with a specific heat of 0.11 cal/g.°C absorbs 82.5 calories of heat and its temperature increases from 20 °C to 25 °C.
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D
Question 2
What are the coefficients needed to balance this chemical equation?
___O₂ → CO₂ +___ H₂O
C₂H5OH +_
O 6, 2, 6, 4
O 6, 6, 2,4
O 1, 3, 2, 3
1, 2, 2, 1
2 pts
Hello and Good Morning/Afternoon:
Original Question: C₂H₅OH + __O₂ → __CO₂ + __ H₂O
To balance this equation:
⇒ must ensure that there is an equal number of elements on both sides of the equation at all times
Let's start balancing:
On the left side of the equation, there are 2 carbon molecule⇒ but only so far one on the right side
C₂H₅OH + __O₂ → 2CO₂ + __ H₂O
On the left side of the equation, there are 6 hydrogen molecules⇒ but only so far two on the right side
C₂H₅OH + __O₂ → 2CO₂ + 3H₂O
On the right side of the equation, there are 7 oxygen molecules⇒ but only so far three on the left side
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
Let's check and make sure we got the answer:
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
2 Carbon ⇔ 2 Carbon
6 Hydrogen ⇔ 6 Hydrogen
7 Oxygen ⇔ 7 oxygen
Thefore the coefficients in order are:
⇒ 1, 3, 2, 3
Answer: 1,3,2,3
Hope that helps!
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A man walks from point A to B at an average speed of 1.0 m/s and immediately returns at anaverage speed of 1.5 ms -1 .What is the average speed for the round trip?
The average speed of the round trip is 1.25 m/s.
What is the average speed of the journey?The average speed of the round trip journey is obtained by taking the average of the forward and return speed of the journey.
Average speed = initial speed + final speed/2Average speed = 1.0 + 1.5/2 = 1.25 m/s
In conclusion, the average speed of the round trip is the average of the initial and final speeds.
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A cart is being pulled forward by a hanging mass. What is the value of the change in its kinetic energy, ΔEk?
Positive
Zero
Negative
The value of change in kinetic energy, ΔEk when a cart is being pulled forward by a hanging mass is Positive
In order words, ΔEk in the above question is positive
What is kinetic energy?Kinetic energy can be defined as the energy a body possess when the body is in motion or due its motion
In conclusion, the value of change in kinetic energy, ΔEk when a cart is being pulled forward by a hanging mass is Positive
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Set local ground level to 700 ft, and record the inches of mercury.
What is the altimeter reading in inches of mercury (from the Kollsman window)?
The altimeter reading is 29.17 from the Kollsman window is 29.17 in Hg
How to determine the altimeter reading?The given parameters are:
Ground level = 700 ft i.e. the field elevationPressure altitude = 1450 ftThe pressure altitude is calculated as:
Altitude = (29.92 – Altimeter reading) * 1,000 + Ground level
Substitute the known values
1450 = (29.92 - Altimeter reading) * 1000 + 700
Subtract 700 from both sides
750 = (29.92 - Altimeter reading) * 1000
Divide through by 1000
0.75 = 29.92 - Altimeter reading
Evaluate the like terms
Altimeter reading = 29.17
Hence, the altimeter reading is 29.17 from the Kollsman window is 29.17 in Hg
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Vanessa made a list comparing the differences between the outer coverings in plants and animals, but she made a mistake. Read the table and then choose the statement that explains why the list is incorrect. Structure Description of Function Spines Protects the plant from predators and helps increase water loss Skin Protects the animal from changes in weather and its environment The skin is a reproductive organ. The skin offers little protection against the weather. The spines attract predators. The spines help decrease water loss.
The skin is NOT a reproductive organ and the spines attract predators are the incorrect statements.
Why the list is incorrect?The list is incorrect because skin is not a reproductive organ and the spines do not attract predators towards each other. Skin protects the body from the outer environment whereas the spines repel the predators from the plant body.
So we can conclude that the skin is NOT a reproductive organ and the spines attract predators are the incorrect statements.
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What is standard one kilogram ?
Answer:
As of the 2019 redefinition of the SI base units, the kilogram is defined in terms of the second and the metre, both based on fundamental physical constants.
It is defined as the mass of a particular international prototype made of platinum-iridium and kept at the International Bureau of Weights and Measures. It was originally defined as the mass of one liter (10-3 cubic meter) of pure water. At the Earth's surface, a mass of 1 kg weighs approximately 2.20 pounds ( lb ).
Explanation:
What is the maximum height that the water would reach in the internal network of a building, without the use of a pump, if the pressure at the sidewalk level is 1.3 kgf/cm2? (density of water 1000 kg/m3)
The maximum height to be reached by the water at the given pressure is 13 m.
Maximum height reached by the water
The maximum height to be reached by the water is calculated as follows;
P = ρgh
where;
P is the pressure of the waterρ is the density of the waterg is acceleration due to gravityh is the maximum height1 kgf/cm² = 98066.5 Pa = 98066.5 N/m²
1.3 kgf/cm² = 127486 N/m²
h = P/ρg
h = (127486)/(1000 x 9.8)
h = 13 m
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Two forces F1=20N and F2=30N are acting on an object as shown in figure: F1=20N F2=30N (i) Find the net force acting on the object? (ii) State the direction of the net force acting on the object? (iii) If the body still does not move under the application of these forces, what can be the possible reason for this? Identify the name of this extra force and its direction. Two forces F1 = 20N and F2 = 30N are acting on an object as shown in figure : F1 = 20N F2 = 30N ( i ) Find the net force acting on the object ? ( ii ) State the direction of the net force acting on the object ? ( iii ) If the body still does not move under the application of these forces , what can be the possible reason for this ? Identify the name of this extra force and its direction .
The net force is the 10N force and its direction is towards F2 force.
What is resultant force?The resultant force or the net force is the actual force that acts on a body. We are told that the two forces act in opposite directions hence the net force is F2 - F1 = 30 N - 20 N = 10 N.
ii) The direction of this net force is going to be towards the 30N force.
iii) If the body does not move under the application of these forces then the F1 force must be reinforced by another force which balances it against the F2 force.
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Which of these must be the same on both
sides of a balanced chemical equation?
A the number of atoms
B
the number
C the number
D the number of solids, liquids, and gases
of compounds
of molecules
Answer:
the total number of atoms of each element present is the same on both sides of the equation. (if I remember correctly)
Farsightedness is corrected with a ___ lens.
Farsightedness is corrected with a convex lens. The correct answer is a convex lens.
The center and edges of a convex lens alternate in thickness. Convergence or focus of the light rays caused by the passage of light through a convex lens aids in projecting the picture onto the retina of the eye. As a result, the person can see items in their immediate surroundings more clearly and the greater focus length of the eye is balanced.
In order to have a positive focal length, a convex lens must be thicker in the middle and narrower in the corners. A convex lens causes light to bend inward and towards its center as it travels through it. By bending the light, the focal point is brought closer to the lens and helps to focus the incoming light rays.
Hence, farsightedness is corrected with a convex lens. The correct answer is a convex lens.
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For the circuit shown in the figure, the switch S is initially open and the capacitor is uncharged. The switch is then closed at time t = 0. How many seconds after closing the switch will the energy stored in the capacitor be equal to 50.2 mJ?
Hi there!
To start, we can use the equation for the charge of a capacitor versus time.
[tex]q(t) = C\epsilon (1 - e^{-\frac{t}{\tau}})[/tex]
[tex]q(t)[/tex] = Charge on capacitor vs. time
[tex]\epsilon[/tex] = EMF of battery (40 V)
**Note: 'Cε' is equal to the MAXIMUM CHARGE on a capacitor.
Where the time constant is given as:
[tex]\tau = RC[/tex]
[tex]\tau[/tex] = Time Constant (s)
[tex]R[/tex] = Resistance (0.5 MΩ)
[tex]C[/tex] = Capacitance (90 μF)
Let's first convert the given units to the necessary 'J', 'Ω' and 'F' to make things easier:
[tex]J = 50.2 mJ[/tex]
[tex]50.2 mJ * \frac{0.001J}{1mJ} = 0.0502 J[/tex]
[tex]R = 0.5 M\Omega\\\\0.5M\Ohm * \frac{1000000\Omega}{1M\Ohm} = 500000\Omega[/tex]
[tex]F = 90 \mu F[/tex]
[tex]90 \mu F * \frac{0.000001 F}{1\mu F} = 0.00009 F[/tex]
Now, let's calculate the time constant.
[tex]\tau = RC = (500000)(0.00009) = 45 s[/tex]
Time to use the equation for energy stored in a capacitor:
[tex]E_C = \frac{1}{2}\frac{Q^2}{C}[/tex]
Our 'Q' varies with time, so:
[tex]E(t)= \frac{1}{2}\frac{( C\epsilon (1 - e^{-\frac{t}{\tau}}))^2}{C}\\\\E(t) = \frac{1}{2}\frac{( C^2\epsilon^2 (1 - e^{-\frac{t}{\tau}})^2)}{C}\\\\E(t) = \frac{1}{2}( C\epsilon^2 (1 - e^{-\frac{t}{\tau}})^2)[/tex]
Let's now plug values into our equation.
[tex]0.0502 = \frac{1}{2}(0.00009)(40^2) (1 - e^{-\frac{t}{45}})^2[/tex]
Simplifying:
[tex]0.697 = (1 - e^{-\frac{t}{45}})^2[/tex]
Take the square root of both sides.
[tex]0.835 = 1 - e^{-\frac{t}{45}}\\\\ e^{-\frac{t}{45}} = 0.165[/tex]
Take the natural log of both sides.
[tex]-\frac{t}{45} = ln(0.165) \\\\\frac{t}{45} = 1.802\\\\t = \boxed{81.08 s}[/tex]