Answer:
i) 8.82 * 10^15 J
ii) 1.8 * 10^23 watts
iii) 1.102 * 10^9 number of cups
iv) 2.450 * 10^6 number of months
Explanation:
i)Total possible energy released
Mtotal = x + x
= 2x * 10 ^-3 kg
when we apply the famous Einstein's formula for mass-energy equivalence
E = Mtotal * c^2
c = speed of light in free space = 3 * 10^8 m/s^-1
x = 49 g
therefore the Total energy released
E = ( 2 * 49 * 10^-3 ) * ( 3* 10^8 ) ^2 = 8.82 * 10^15 J
ii) power output
x in ns = 49 * 10^-9 s
therefore energy released per sec = Total energy released / 49 * 10^-9
= (8.82 * 10^15 ) / ( 49 * 10^-9 ) = 1.8 * 10^23 J
hence power output = 1.8 * 10^23 J * s^-1 = 1.8 * 10^23 watts
iii) Calculate the number of cups
Total energy obtained in a cup = 8 MJ = 8* 10^6 J
number of cups required to match of the Total energy released
n = Total energy released / energy obtained in a cup
= ( 8.82 * 10^15 ) / ( 8 * 10^6 ) = 1.102 * 10^9 number of cups
iv) Calculate the number of months
n = Total energy released / energy obtained in a month
= (8.82 * 10^15 ) / ( 3.6 * 10^9) = 2.450 * 10^6 number of months
A bug walking on the circular rim of a flower
pot completes one lap around the planter in
8.667 s.
If the radius of the planter is 13.9 cm, how
fast was it traveling?
Given parameters;
Time taken to complete a lap = 8.667s
Radius of flower = 13.9cm
convert to SI unit of m, 100cm = 1m
13.9cm gives [tex]\frac{13.9}{100}[/tex] = 0.139m
Unknown = speed
To solve this problem, we need to first find the circumference of the flower.
Circumference of the circular flower = 2 π r
where r is the radius of the flower;
Circumference = 2 x 3.142 x 0.139 = 0.87m
Now to find the how fast the bug is travelling,
Speed = [tex]\frac{distance}{time}[/tex]
Since the bug covered 1 lap, the distance is 0.87m
Now input the parameters and solve for speed;
Speed = [tex]\frac{0.87}{8.667}[/tex] = 0.1m/s
The bug is travelling at a speed of 0.1m/s
What is the displacement of a student who walks 12 m North, 5 m West, 3 m South,
and finally 6 m West to get to his next class?
When you draw all 4 of those moves, you see that he winds up 9m North and 11m West of where he started.
So the magnitude of his displacement is
D = √(9² + 11²) m²
D = √(81 + 121) m²
D = √(202) m²
D = 14.2 m
The direction is arctan(-11/9) = 50.7° west of North
what are the chemical symbols for carbon aluminium hydrogen oxygen and sodium
El unico que se es el del oxígeno: o2
Halfway through Mila's run, when the music stopped playing, was there energy in Mila's phone? What is your
evidence?
Answer:
No energy
Explanation:
"How did your current and voltage measurements differ between the series and parallel circuits you created
Answer:
Series circuit:
The voltage that is measured across the circuit is different.
The current measured in a series circuit remains the same at all points in the circuit.
Parallel circuit:
The current measured across each resistor varies
The voltage measured across a parallel circuit will remain the same
Explanation:
Series and parallel circuits behave differently when it comes to the circulation of current and the interaction with a potential difference.
In a series circuit, the resistances are connected end to end. As a result, the voltage that is measured across the circuit is different once resistance is encountered. However, the current measured in a series circuit remains the same at all points in the circuit.
A parallel circuit behaves in an exactly opposite manner to the series circuit. In a parallel circuit, the resistances are connected side by side. As a result of this, the current measured across each resistor varies as there are circuit branches through which electric current can flow into. On the other hand, the voltage measured across a parallel circuit will remain the same
You and your friend Peter are putting new shingles on a roof pitched at 25 ∘ . You're sitting on the very top of the roof when Peter, who is on the edge of the roof, 5.4 m away, asks you for the box of nails. Rather than carry the 2.4 kg box of nails down to Peter, you decide to give the box a push and have it slide down to him. Part A If the coefficient of kinetic friction between the box and the roof is 0.51, with what speed should you push the box to have it gently come to rest right at the edge of the roof?
Answer:
Explanation:
Frictional force acting on the box = mg cos 25 x μ where μ is coefficient of friction
= 2.4 x 9.8 x cos 25 x .51 = 10.87 N
Weight of the box acting along the incline = mg sin 25 = 9.94 N
Net force = 10.87 - 9.94 = .93 N . It will create a deceleration of .93 / 2.4
= .3875 m /s² in the box.
v² = u² - 2 a s
v = 0 , a = .3875 , s = 5.4 m
= = u² - 2 x .3875 x 5.4
u = 2.045 m /s
The dipole moment of water is p = 6.17 x 10-30 C m. If the electric field in a microwave oven is on average 94.7 x 10-6 N/C, and water molecules start anti-parallel to the external field (180o), how much energy (in Joules) is deposited into a water sample in 2.39 seconds with 13.1 of water if the direction of this field switches every 3.42 x 108 times a second and each time the electric field flips the water molecules align themselves with the new direction?
Answer:
Explanation:
Given that:
p = 6.17 × 10⁻³⁰ Cm
Electric field E = 94.7 × 10⁻⁶ N/C
Then:
[tex]U= -p^{\to} *E^{\to}[/tex]
[tex]U_i = -pE \ cos180^0 =pE \\ \\ U_f = -pE \ cos 0^0 = -pE[/tex]
∴
[tex]\Delta U = U_i - U_f = 2pE \ \ per \ dilute/per \ switch[/tex]
This implies that one switch of dipole produces 2pE energy to be deposited in the water.
mass of water = 13.1 g
The number of water molecule = [tex]\dfrac{mass}{molar \ mass}\times N_A[/tex]
=[tex]\dfrac{13.1}{18.015}\times6.023 \times 10^{23}[/tex]
= 4.38 × 10²³ molecules of water.
∴ Number of dipoles = 4.38 × 10²³
The total number of switches in 2.39 sec = switch frequency × 2.73
Number of switches = 2.39 × 3.42 × 10⁸
Number of switches = 817380000
Number of switches = 8.174 × 10⁸
The total energy Q deposited = Energy deposited per dipole × Number of dipole × no of switches
Q = (2pE) × 4.38 × 10²³ × 8.174 × 10⁸
Q = (2 × 6.17 × 10⁻³⁰ × 94.7 × 10⁻⁶ × 4.38 × 10²³ × 8.174 × 10⁸ )
Q = 0.41838 J
Determine an example of a social influence.
a brother or sister
your best friend
a community leader
All are social influences.
Answer:
all are social influences
An example of a Natural electric field is
Answer:
Lightning
Explanation
Real-world efficiencies are generally very high, in the 90 percent range. Please select the best answer from the choices provided. T F
Answer:
t
Explanation:
Answer: true
Explanation:
Sandstone is a sedimentary rock. Which two processes cause sand particles to form sandstone?
1. cementation and cooling
2.compaction and cementation
3.cooling and erosion
4.erosion and heating
Answer:
Compaction and cementation
Explanation:
Cementation: As ions are deposited by fluids to form a compound that hardens loose sedimentary rocks.
Compaction: As the density of sedimentary rocks on edge of them are forced together through sediments.
Answer:
number 2 is correct
Explanation:
cementation as icons are deposited by fluids to form a compound that hardens looses sedimentary rocks .
compaction is the density of sedimentary rocks on edge of them, are forced together though sediments mark me brainest add and follow me
Pots A and B both have plain soil, bean seeds, and the same amount of light. Pot B receives more water (see table). After 50 days the plants are measured. Based on the data, what is the correct conclusion?
The amount of water affects the mass and the height of the plants.
What is the correct conclusion from the data obtained?The correct conclusion is the conclusion which the data obtained supports.
Plants need both water and sunlight to grow.
The variation the amount of water or sunlight that a plant receives will affect the growth rate of the plant.
Based on the data obtained from the experiment where Pots A and B both have plain soil, bean seeds, and the same amount of light, while Pot B receives more water, the amount of water affects the mass and the height of the plants.
In conclusion, plants need both water and sunlight for growth.
Learn more about water and sunlight at: https://brainly.com/question/444493
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A boat Is headed due north on a river that's flowing directly east. What is the general direction of travel for this boat with respect to the land?
A. southeast
B. northeast
C. northwest
D.
east
Answer:
Its northeast. Just took the exam.
Explanation:
Answer:
See image
Explanation:
Plato
A wildebeest and a chicken participate in a race over a 2.10 km long course. The wildebeest travels at a speed of 19.0 m/s and the chicken can do 3.30 m/s. The wildebeest runs for 1.680 km and then stops to tease the slow-moving chicken, which eventually passes by. The wildebeest waits for a while after the chicken passes and then runs toward the finish line. Both animals cross the finish line at the exact same instant. Assume both animals, when moving, move steadily at their respective speeds.
(a) how far (in m) is the chicken from the Finish Line when the wildebeest resume the race?
(b) for how long in time (in s) was the wildebeest stationary?
Answer:
Explanation:
2.1 km = 2100 m
1.68 km = 1680 m
a ) Time taken by wild beast to travel 1680 m
= 1680 / 19 = 88.42 s
Time taken by wild beast to travel 2100 m
2100 / 19 = 110.52 s
distance travelled by chicken in 88.42 s
= 88.42 x 3.3 = 291.78 s
Its distance from the end point
= 2100 - 291.78 = 1808.22m
b ) Time taken by chicken to travel 2100 m
= 2100 / 3.3 = 636.36 s
Both reach simultaneously so , time of resting by wild beast
= 636.36 - 110.52 = 525.84 s .
What is the difference between environmental science and environmentalism?
Explanation:
Environmental science is the pursuit of knowledge about the workings of the environment and our interactions with it. Environmentalism is a social movement dedicated to protecting the natural world. Nature makes resources at similar speeds
A Tennis ball falls from a height 40m above the ground the ball rebounds
with 0.5 of the velocity with which it strikes the ground. If the ball rebound
with 1/2 of the velocity with which the balls strike the ground any time the
ball striked the ground. Calculate
[i] the position of the ball after 5s from the ground
[iiafter how many bounds will the ball remain on the ground
(iii) what is the time interval between the third and fourth bounds
(iii) predicts the velocity of the ball after 6s
If the ball is dropped with no initial velocity, then its velocity v at time t before it hits the ground is
v = -g t
where g = 9.80 m/s² is the magnitude of acceleration due to gravity.
Its height y is
y = 40 m - 1/2 g t²
The ball is dropped from a 40 m height, so that it takes
0 = 40 m - 1/2 g t²
==> t = √(80/g) s ≈ 2.86 s
for it to reach the ground, after which time it attains a velocity of
v = -g (√(80/g) s)
==> v = -√(80g) m/s ≈ -28.0 m/s
During the next bounce, the ball's speed is halved, so its height is given by
y = (14 m/s) t - 1/2 g t²
Solve y = 0 for t to see how long it's airborne during this bounce:
0 = (14 m/s) t - 1/2 g t²
0 = t (14 m/s - 1/2 g t)
==> t = 28/g s ≈ 2.86 s
So the ball completes 2 bounces within approximately 5.72 s, which means that after 5 s the ball has a height of
y = (14 m/s) (5 s - 2.86 s) - 1/2 g (5 s - 2.86 s)²
==> (i) y ≈ 7.5 m
(ii) The ball will technically keep bouncing forever, since the speed of the ball is only getting halved each time it bounces. But y will converge to 0 as t gets arbitrarily larger. We can't realistically answer this question without being given some threshold for deciding when the ball is perfectly still.
During the first bounce, the ball starts with velocity 14 m/s, so the second bounce begins with 7 m/s, and the third with 3.5 m/s. The ball's height during this bounce is
y = (3.5 m/s) t - 1/2 g t²
Solve y = 0 for t :
0 = (3.5 m/s) t - 1/2 g t²
0 = t (3.5 m/s - 1/2 g t)
==> (iii) t = 7/g m/s ≈ 0.714 s
As we showed earlier, the ball is in the air for 2.86 s before hitting the ground for the first time, then in the air for another 2.86 s (total 5.72 s) before bouncing a second time. At the point, the ball starts with an initial velocity of 7 m/s, so its velocity at time t after 5.72 s (but before reaching the ground again) would be
v = 7 m/s - g t
At 6 s, the ball has velocity
(iv) v = 7 m/s - g (6 s - 5.72 s) ≈ 4.26 m/s
most of our brains activity is:
If a car has a mass of 1,300 kg and is moving at a constant velocity of 20 m/s, what is the net force acting on the car?
Constant velocity means there is no acceleration in the direction of the car's movement and hence no force acting on the car in this direction.
The only forces acting on the car are due to gravity and the Earth pushing back up on the car. But the car doesn't move up or down, so the net force is 0.
a coin with a diameter of 2.1 cm with an initial angular speed of 19 rad/sec and rolls in a straight line. The rotation slows at an angular acceleration of magnitude 1.9 rad/s^2. What is the magnitude of the linear acceleration?
Answer:
the magnitude of the linear acceleration is [tex]=1.995 \,\,cm/s^2\\[/tex]
Explanation:
Recall that the linear acceleration (a) is associated with the angular acceleration vi the formula:
[tex]a=R\,\alpha[/tex]
where R stands for the radius of the rotational motion (in our case 2.1 cm/2 = 1.05 cm, and [tex]\alpha[/tex] stands for the angular acceleration in radians per units of time squared.
Then the linear acceleration in our case is:
[tex]a=R\,\alpha\\a=1.05 cm * (1.9\,\,\,rad/s^2)\\=1.995 \,\,cm/s^2[/tex]
How is electrolysis used in order to prevent materials from corrosion or rusting?
Answer:
We use electrolysis to prevent a material from rusting,
The metal forms a coating around the material and hence prevents any contact between the material and the environment
This process also gives us the physical strength of the material and the aesthetic properties of the coated metal
the metal commonly used to coat the object is Zinc and the process is called galvanisation
Jason took 6 hours to travel 540 km. For the first 140 km, he
took 2 hours. What was his average speed for the rest of the
journey?
km/h
Answer: 100
Explanation:
Consider the Bell X-2 research aircraft, which was the first aircraft to achieve Mach 3 on September 27th , 1956. During this flight, the aircraft reached a velocity of 936 m/s at an altitude of 65,500 ft. Calculate the actual Mach number that the X-2 achieved during this flight. Now, consider two other conditions. Condition #1: Assuming the aircraft travels at the same velocity in Jupiter’s atmosphere at an altitude where the temperature is -145 °C. Also, assume that the atmosphere of Jupiter is made up of entirely hydrogen gas (H2) which has a molecular weight of 2.016 g/mol. Calculate the Mach number of the X-2 on Jupiter. Condition #2: Assuming the aircraft travels at the same velocity in Pluto’s atmosphere at an altitude where the temperature is -223 °C. Also, assume that the atmosphere of Pluto’s is made up of entirely nitrogen gas (N2) which has a molecular weight of 28.013 g/mol. Calculate the Mach number of the X-2 on Pluto.
Answer:
Explanation:
mach number is ratio of speed with respect to speed of sound .
speed of aircraft = 936 m /s
speed of sound at 65500 ft = 295 m /s
mach number = 936 / 295 = 3.17
velocity of sound at - 145 degree and in hydrogen gas .
velocity of sound
[tex]V=\sqrt{\frac{RT}{M} }[/tex]
[tex]V=\sqrt{\frac{8.3\times(273-145)}{2\times10^{-3}} }[/tex]
= 729 m /s
mach number
= 936 / 729 = 1.28
velocity of sound at - 223 degree and in nitrogen gas .
velocity of sound
[tex]V=\sqrt{\frac{RT}{M} }[/tex]
[tex]V=\sqrt{\frac{8.3\times(273-223)}{28.013\times10^{-3}} }[/tex]
= 122 m /s
mach number
= 936 / 122 = 7.67
Assuming all object are moving with the same velocity, witch statement describes the object with the largest intertia?
Answer:
Mass is the quantitative measure of inertia of any object.
Explanation:
The object that have largest mass will have largest inertia as well as largest momentum.
Identify the atom
Ве
C
H
Не
Answer:
Be: Beryllium
C: Carbon
H: Hydrogen
He: Helium
Use the picture to answer the question.
A red striped bowling ball with 3 finger holes.
Name at least three physical properties of the bowling ball.
Answer:
The physical properties is hardness shape and color, I choose hardness because I have grabbed bowling balls before and they are very hard well there could be different types of bowling balls made of different things but I have never seen one or toughed a bowling ball that is not hard. Another physical property I chose for the bowling ball was shape, The reason I chose shape was because the bowling ball is circle, the actual name for a 3-D circle is sphere. The last physical property for a bowling ball is color because mostly all bowling balls have color for example the one in the picture it is red with a little bit of pink, there is many different bowling balls that have different color different hardness but NOT different shape. That is the physical properties of a bowling ball.
Explanation:
Answer: The bowling ball is round in shape and red in color. The bowling ball is smooth and hard.
Explanation:
did it on edge
The USC Trojan football team bus is heading to an away game, traveling on a long, straight road at a constant speed of 28.0 m/s. All of a sudden, at t = 0, a car full of students from the opposing team cuts in front of the bus, at a mere distance of 70.0 m ahead of the bus, moving in the same direction with a constant velocity of 6.00 m/s. The panic brake deceleration of the bus is 3.00 m/s2 . a) (10 Points) If the bus begins braking at t = 0, how much time will elapse until the bus and car collide? b) (5 Points) How far down the road, from the original position of the bus, will the collision occur? c) (10 Points) What would the acceleration of the bus have to be for the collision to be avoided?
Answer:
a. 17.34 s. b. 104.51 m c. -7.16 m/s²
Explanation:
a. The distance, d moved by the car at constant speed v = 6.00 m/s in time t which they collide is d = vt. The distance d' moved by the bus from its initial position 70 m away from the car with a constant velocity u = 28.0 m/s and deceleration a = -3.00 m/s² is d' = 70 + ut + 1/2at².
At collision, s = d
vt = 70 + ut + 1/2at²
substituting the values of the variables, we have
6t = 70 + 28t + 1/2(-3)t²
6t = 70 + 28t - 1.5t²
collecting like terms, we have
1.5t² + 6t - 28t - 70 = 0
1.5t² - 22t - 70 = 0
using the quadratic formula to find t, we have
[tex]t = \frac{-(-22) +/- \sqrt{(-22)^{2} - 4 X -70 X 1.5} }{2 X 1.5} \\t = \frac{22 +/- \sqrt{484 + 420} }{3} \\\\t = \frac{22 +/- \sqrt{904} }{3} \\\\t = \frac{22 +/- 30.01 }{3} \\\\t = \frac{22 - 30.01 }{3} or \frac{22 + 30.01 }{3} \\t = \frac{-8.01 }{3} or \frac{52.01 }{3} \\\\t = -2.67 s or 17.34 s[/tex]
We take the positive value.
So t = 17.34 s.
So, 17.34 s elapses before the bus and car collide.
b. Since the distance covered by the bus is d' = 70 + ut + 1/2at², this is how far down the road the collision occurs.
Substituting the values of the variables, we have
d' = 70 + 28 m/s × 17.34 s + 1/2(-3 m/s²)(17.34)²
d' = 70 + 485.52 - 451.01
d'= 104.51 m
c. To just avoid the collision, the bus must decelerate in the distance of 104.51 m from the car to the speed of the car. So using
v² = u² + 2ad' where v = 6.00 m/s, u = 28.0 m/s and d' = 104.51 m
the acceleration is thus
a = (v² - u²)/d'
a = ((6 m/s)² - (28 m/s)²)/104.51 m
a = (36 m²/s² - 784 m²/s²)/104.51 m
a = -748 m²/s² ÷ 104.51 m
a = -7.16 m/s²
Use an ideal op amp to design a differentiation circuit for which the time constant is 10‐3s usinga 10 nF capacitor. What are the gains and phase shifts found for the circuit at one‐tenth and 10times the unity‐gain frequency? A series input resistor is added to limit the gain magnitude athigh frequencies to 100 V/V. What is the associated 3‐dB frequency? What gain and phase shiftresult at 10 times the unity‐gain frequency?
Answer:
Attached below is the detailed solution
Gains at one-tenth unity gain = 0.1 v/v
Gains at 10 times unity gain = 10 v/v
phase shift at 10 times unity gain =-95.71⁰
Explanation:
a)Gain at one-tenth unity gain
w/Wc = 100/1000 = 0.1 v/v
b)Gain at 10 times unity gain
w / Wc = 10 krad/sec / 1 krad/sec = 10 v/v
3-db frequency of new differentiator = 15.915 khz
attached below is the detailed solutions
A radar station sends a signal to a ship which is located a distance 13.9 kilometers from the station at bearing 136° clockwise from the north. At the same moment, a helicopter is at a horizontal range of 19.6 kilometers, at bearing 152° clockwise from the north, with an elevation of 2.57 kilometers. Let east be the î direction, north be the ĵ direction, and up be the direction.
(A) What is the displacement vector (in km) from the helicopter to the ship? (Express your answer in vector form. Do not include units in your answer.)
(B) What is the distance (in km) between the helicopter and ship?
(C) The ship begins to sink at a rate of 5.40 m/s. Write the position vector (in km) of the ship relative to the helicopter as a function of time as the ship sinks. Assume that the helicopter remains hovering at its initial position and that the sinking rate remains the same even after the ship sinks under the surface. (Use the following as necessary: t. Do not include units in your answer.)
(D) Evaluate the position of the ship relative to the helicopter (in km) after 1.90 h. (Express your answer in vector form. Do not include units in your answer.)
Answer:
A) d = 7.9267 km, θ = 157.19
D) d = 35.17 km
Explanation:
For this exercise the easiest way is to decompose the vectors
Ship
X axis (North)
The angle measured from the positive side of the x axis (unit vector i^ ) counterclockwise
θ = 136- 136 = 224
cos θ = x₁ / 13.9
x₁ = 13.9 cosc 224
x₁ = - 9.9988 103 m
z axis
sin 224 = z₁ / 13.9
z₁ = 13.9 sin224
z₁ = -9.6558 m
Axis y
y₁ = 0
Helicopter
x-axis (North)
θ = 360 - 152
θ = 208
cos θ = x₂ / 19.6
x₂ = 19.6 cos 208
x₂ = -17.3058 km
z axis
sin 204 = z₂ / 19.6
z₂ = 19.6 sin 204
z₂ = -7.9720 km
Axis y
y₂ = 2.57 km
It's a bit strange the way the axes give, but having the decomposition of the vectors we can answer the questions
A) They ask the displacement vector, let's start looking for the distance
d = √ [(x₂-x₁)² + (y₂-y₁)² + (z₂-z₁)²]
we substitute
d =√[(17.3058 - 9.9988)² + (2.57 - 0)² + (7.9720 -9.6558)²]
d = √ [7.307² + 2.57² + 1.6838²]
d = 7.9267 km
the angle of this vector is with respect to North (x-axis)
cos θ = -7.307 / 7.9267
θ = cos⁻¹ (-0.9218)
θ = 157.19
Y-axis elevation angle
cos θ'= 2.57 / 7.9267
θ’= cos⁻¹ (0.3242)
θ’= 71.09
b) d = 7.9267 km
c) at this time the ship is sinking at constant speed, the sinking direction is the same vertical direction of the helicopter (y-axis)
the distance is
y₁ = v₁ t
let's reduce speed to km /h
v₁ = 5.4 m / s (1km/1000m ) (3600s/1h)= 19.44 km /h
y₁ = 19.44 t
the vector positions is
d = √ [(x₂-x₁)² + (y₂-y₁)² + (z₂-z₁)²]
d = √ [7.307² + (2.57 -19.44 t)² + 1.6838²]
in vertical angle is
cos θ'= (2.57 -19.44t) / d
At an angle to the x axis is
cos θ = -7.307 / d
d) let's evaluate the position for t = 1.90 h
distance
d = √ [7.307² + (2.57- 19.44 1.9)² + 1.6838²]
d = √ [7.307² + (-34.366)² + 1.6838²]
d = 35.17 km
A certain lightning bolt moves 50.0 C of charge. How many units of fundamental charge is this?
question 8 how to do
Answer:
We know that the resistance of a material is its length divided by its cross-sectional area and all that multiplied by its resistivity
Hence, resistance = ρ * length(in m) / Cross-sectional area
(ρ = constant of resistivity)
If you do not understand cross-sectional area, comment on this answer
since both the wires are made of the same substance, both their resistivity will be the same
since we are told that both the wires have the same resistance,
(ρ * length 1) / cross-sectional area 1 = (ρ * length 2) / cross-sectional area 2
since they both have the same resistivity, both the ρ will cancel out
length 1 / cross-sectional area 1 = length 2 / cross-sectional area 2------(1)
Calculating the cross-sectional area
To simplify it , the cross-sectional area is the area of the circle you can currently see on either of the wire
let the radius of wire 1 = 2r
then, the radius of wire 2 = r
Cross-sectional area 1 = π (2r)^2 = 4πr^2
Cross-sectional area 2 = π (r)^2
Now, using these values in (1)
l / 4πr^2 = l' / πr^2
l / l' = 4πr^2/πr^2
l / l' = 4 / 1
the length of rod 'P' is l
from the equation, we can simplify:
l (length of rod 'P') = 4 l'(length of rod 'Q')
Therefore, we can say that the length of rod 'P' is 4 times the length of rod 'Q'
