Manganese-52 has a half-life of 6 days. How many days would a scientist have to wait for the radioactivity to be 12.5% the starting amount?
Answer:
Let N = N0 where N0 is the number of atoms originally present.
In 6 days N = N0 / 2
In 12 days N = N0 / 4
In 18 days N = N0 / 8 = .125 N0
So it would take 18 days.
Manganese-52 has a half-life of 6 days. a scientist has to wait 18 days for the radioactivity to be 12.5% of the starting amount
What is radioactivity?The ability of some unstable atoms to emit nuclear radiation spontaneously, typically in the form of alpha or beta particles frequently accompanied by gamma rays, is known as radioactivity. This radiation is released when a nucleus undergoes radioactive decay and transforms into a different isotope that may be radioactive (unstable) or non-radioactive depending on the number of neutrons and protons in the nucleus (stable).
As given in the problem statement Manganese-52 has a half-life of 6 days. this means after 6 days Manganese-52 will reduce to its half value
similarly, after 12 days it further reduces to 50% of the previous value which would be 25 %
Similarly, after 18 days, it will reduce 50% from the previous value which comes out to be 12.5 %
Thus, The half-life of manganese-52 is 6 days. It takes 18 days for the radioactivity to drop to 12.5% of the initial level.
Learn more about radioactivity here
https://brainly.com/question/13950350
#SPJ2
the pressure of a gas is 100.0kpa and its volume is 500.0ml if the volume increase to 1000.0ml what is the new pressure of the gas
50Kpa
Explanation:
P1V1 = P2V2
Where;
P1= 100. P2= ?
V1 = 500. V2 = 1000
100 × 500 = P2 × 1000
50000 = 1000P2
50000/1000 = P2
50 = P2
P2 = 50Kpa
Which of these statements partially defines law?
Answer: I dont see the option choices
Explanation:
Consider a metal rod of uniform temperature. Is it possible that heat spontaneously flow from one end of the rod to the other end so that they end up in different temperatures? Why?
Answer:
No its not possible in that yes heat flow is due to temperature different but with time equilibrium in temperature is reached hence there is no temperature difference at both ends at this time
The current through a 0.2-H inductor is i(t) = 10te–5t A. What is the energy stored in the inductor?
Answer:
E = 10t^2e^-10t Joules
Explanation:
Given that the current through a 0.2-H inductor is i(t) = 10te–5t A.
The energy E stored in the inductor can be expressed as
E = 1/2Ll^2
Substitutes the inductor L and the current I into the formula
E = 1/2 × 0.2 × ( 10te^-5t )^2
E = 0.1 × 100t^2e^-10t
E = 10t^2e^-10t Joules
Therefore, the energy stored in the inductor is 10t^2e^-10t Joules
(4) A stainless steel storage tank contains 5 kg of carbon dioxide gas and 7 kg of argon gas. How many kmoles are in the tank?
Answer:
0.2886 Kmoles
Explanation:
Number of moles is calculated by dividing mass of element/molecular mass of element
Mass of Carbon Di oxide = 5000 g or 5 kg
Molecular mass of CO2 = 12 + 16×2 = 44 g
No of moles = 5000/44 = 113.6 moles = 0.1136 Kmoles
Mass of argon = 7Kg or 7000 kg
Molecular mass of Argon(Ar) = 40g
No of moles = 7000/40 = 175 moles = 0.175 Kmoles
Total Kmoles = 0.175+0.1136=0.2886 Kmoles
Bacteria vary somewhat in size, but a diameter of 1.9 m is not unusual.A. What would be the volume (in cubic centimeters) of such a bacterium, assuming that it is spherical?
B. What would be the surface area (in square millimeters) of such a bacterium, assuming that it is spherical?
Answer:
Volume = 3.6 x 10^-12 cm^3
Area = 1.1 x 10^-5 mm^2
Explanation:
The diameter of the bacteria that is in the shape of spherical = 1.9 m
Now we have to find the volume of the bacteria. So, use the below formula to find the volume of bacteria.
Volume = (4πr^3) / 3
Volume = (4/3)* π*(1.9*10^-6 / 2)^3
Volume = 3.6 x 10^-18 m^3
Volume = 3.6 x 10^-12 cm^3
Now find the surface area.
The surface area = 4πr^2
Area = 4 π (1.9/2)62
Area = 1.1 x 106-11 m^2
Area = 1.1 x 10^-5 mm^2
change-22^0f to kelvin?
Answer:
The formula is kelvin = (tempature in farenheit-32) ÷ 1.8 +273.15
So it will be (-22-32) ÷ 1.8 +273.15= 243.15 kelvin
Answer:
T(K) = (T(°F) + 459.67)× 5/9
answer is 243.15
Suppose the U.S. national debt is about $15 trillion. If payments were made at the rate of $1,500 per second, how many years would it take to pay off the debt, assuming no interest were charged? Note: Before doing these calculations, try to guess at the answers. You may be very surprised. yr (b) A dollar bill is about 15.5 cm long. How many dollar bills attached end to end would it take to reach the Moon? The Earth-Moon distance is 3.84 108 m. dollar bills
Answer:
This question has already been answered.
Explanation:
https://brainly.com/question/13542582
Suppose you are asked to compute the tangent of 5.00 meters. Is this possible? Why or why not?
Answer:
Generally it is only possible to compute the tangent of angle in their various unit but because 5 meter is not an angle then it is impossible to compute the tangent of 5 meters.
Explanation:
An athlete completes a round of circular tract with diameter 150 m in 5 min. What is the average speed V of the athlete in m/s? Answer with two decimal places
Answer:
Explanation:
From the question we are told that
The diameter is [tex]d = 150 \ m[/tex]
The time taken is [tex]t = 5 \ min = 300\ s[/tex]
Generally the circumference is mathematically represented as
[tex]C = d * \pi[/tex]
[tex]C = 150 * 3.142[/tex]
[tex]C = 471.3 \ m[/tex]
The average speed is mathematically represented as
[tex]v = \frac{C}{ t}[/tex]
[tex]v = \frac{471.3}{300}[/tex]
[tex]v = 1.571 \ m/s[/tex]
You are an engineer in charge of designing a new generation of elevators for a prospective upgrade to the Empire State Building. Before the state legislature votes on funding for the project, they would like you to prepare a report on the benefits of upgrading the elevators. One of the numbers that they have requested is the time it will take the elevator to go from the ground floor to the 102nd floor observatory. They are unlikely to approve the project unless the new elevators make the trip much faster than the old elevators. If state law mandates that elevators cannot accelerate more than 2.40 m/s2 or travel faster than 18.8 m/s , what is the minimum time in which an elevator can travel the 373 m from the ground floor to the observatory floor
Answer:
t_total = 23.757 s
Explanation:
This is a kinematics exercise.
Let's start by calculating the distance and has to reach the limit speed of
v = 18.8 m / s
v = v₀ + a t₁
the elevator starts with zero speed
v = a t₁
t₁ = v / a
t₁ = 18.8 / 2.40
t₁ = 7.833 s
in this time he runs
y₁ = v₀ t₁ + ½ a t₁²
y₁ = ½ a t₁²
y₁ = ½ 2.40 7.833²
y₁ = 73.627 m
This is the time and distance traveled until reaching the maximum speed, which will be constant throughout the rest of the trip.
x_total = x₁ + x₂
x₂ = x_total - x₁
x₂ = 373 - 73,627
x₂ = 299.373 m
this distance travels at constant speed,
v = x₂ / t₂
t₂ = x₂ / v
t₂ = 299.373 / 18.8
t₂ = 15.92 s
therefore the total travel time is
t_total = t₁ + t₂
t_total = 7.833 + 15.92
t_total = 23.757 s
What is the potential difference ΔVAB Δ V A B ? Express your answer with the appropriate units. problem 21.19
Answer:
30
Explanation:
A mass is tied to a spring and begins vibrating periodically the distance between its highest and lowest position is 48cm what is the amplitude of the vibrating?
Answer 24cm
Explanation:
The amplitude of vibration of the spring is "24 cm"
The periodic vibrating body's motion follows a sinusoidal path. This sinusoidal path is illustrated in the attached picture.
From the picture, it can be clearly seen that the amplitude of the periodic vibration motion is the distance from its mean position to the highest point.
Since the distance of both the highest and the lowest points from the mean position is the same. Therefore, the distance between the lowest and the highest point must be equal to two times the amplitude of the wave.
[tex]Distance\ between\ highest\ and\ lowest\ point = 2(Amplitude)\\\\Amplitude = \frac{Distance\ between\ highest\ and\ lowest\ point}{2}\\\\Amplitude = \frac{48\ cm}{2}\\\\[/tex]
Amplitude = 24 cm
Learn more about the amplitude of the sinusoidal wave (path) here:
https://brainly.com/question/2363891
A typical atom has a diameter of about 1.32 x 10-10 m.
A) What is this in inches?
B) How many atoms are there along a 21.0cm line?
Answer:
A) The value of the diameter in inches is 5.19685 × 10⁻⁹ inches
B) There are 1,590,909,091 atoms on a 21.0cm line
Explanation:
A) To determine what its diameter is in inches
We will convert 1.32 × 10⁻¹⁰ m to inches
First convert this to centimeters (cm)
1.32 × 10⁻¹⁰m = 1.32 × 10⁻¹⁰ × 10² cm
= 1.32 × 10⁻⁸cm
Now, since 1 inch = 2.54 cm
∴ 1 cm = [tex]\frac{1}{2.54}[/tex] inches
If 1 cm = [tex]\frac{1}{2.54}[/tex] inches
Then 1.32 × 10⁻⁸ cm will be
1.32 × 10⁻⁸ × [tex]\frac{1}{2.54}[/tex] inches
= 5.19685 × 10⁻⁹ inches
This is the value of the diameter in inches
B) For the number of atoms on a 21.0cm line
The diameter of 1 atom is 1.32 × 10⁻¹⁰m
1.32 × 10⁻¹⁰m = 1.32 × 10⁻⁸cm
Hence, on a 21.0 cm line, we will have
(21.0 / 1.32 × 10⁻⁸) atoms
= 1590909091 atoms
Hence, there are 1,590,909,091 atoms on a 21.0cm line
In a ballistic pendulum experiment, suppose the digital timer shows 0.02 s for the time of flight of the projectile. The manufacturer information about the precision of the timer is nowhere to be found. What error would you quote on your measurement
Answer:
The value is [tex]\Delta t = 0.01 \ s[/tex]
Explanation:
From the question we are told that
The time of flight is [tex]T = 0.02 \ s[/tex]
Given that the value of the time of flight is in three decimal place then the error quote is
[tex]\Delta t = 0.01 \ s[/tex]
What does the law of universal gravitation describe? The motion of the planets around the sun The observation that matter cannot be created or destroyed The observation that all objects that have mass attract each other The amount of force acting on an object being equal to its mass times its acceleration
yes its The observation that all objects that have mass attract each other
A physics student runs along a line tangent to the edge of a motionless merry-go-round and jumps on at the very outside. The merry-go-round has the shape of a uniform disk.
A) Make an angular momentum chart to help you keep track of what is and is not changing. Consider the two objects, the student and merry-go-round, with the total angular momentum of these two objects conserved. Must the student have angular momentum before jumping on the merry-go-round?
B) Is linear momentum conserved in this interaction if you just consider the merry-go-round and the student?
Answer:
We know that angular momentum is mvr
So that of the students initially will be
A1= mvr
and the final of the student and the merrygo round will be
A2= (1/2Mr²+mr)omega
So
Angular velocity (omega)= mvr/(1/2Mr²+mr)
This is the final angular velocity of the system so yea the student must have angular momentum before jumping on the merry-go-round
B. Because of directional changes at every edge of the Merry go round that result in changes in velocity, this results in changes in momentum too thus linear momentum is not conserved
all digits shown on the measuring device, plus one estimated digit. are consided what
Answer:
The significant figures in a measurement consist of all the certain digits in that measurement plus one uncertain or estimated digit. In the ruler illustration below, the bottom ruler gave a length with 2 significant figures, while the top ruler gave a length with 3 significant figures.
Explanation:
A metre rule balances when the 50 cm mark is directly above a pivot. State where in the rule its centre of mass is located?
Answer:
The ruler's center of mass is located on the vertical line defined by the 50 cm mark.
Explanation:
Recall that in order to have equilibrium as that described by this example, the net Torque in the ruler should be zero. which means in our case that the weight due to the right half of the ruler, should equal in absolute value of the weight of the left side of the ruler, thus defining where the ruler's center of mass is.
Since this happens at the mark 50 cm, then the center of mass of the ruler is located somewhere inside the ruler somewhere above where the pivot is located (50 cm mark)
The unknown vector v satisfies b - v = λ and b x v-c, where λ, b, and c are fixed and known. Find v in terms of λ, b, and c.
differences between Constant velocity and constant acceleration
Answer:
Traveling with a constant velocity means you're going at the same speed in the same direction continuously. If you have a constant velocity, this means you have zero acceleration. ... If you travel with a constant acceleration, your velocity is always changing, but it's changing by a consistent amount each second.
A sinusoidal electromagnetic wave from a radio station passes perpendicularly through an open window that has area of 0.700 m2 . At the window, the electric field of the wave has an rms value 0.0400 V/m .
How much energy does this wave carry through the window during a 30.0-s commercial?
Express your answer with the appropriate units.
Answer:
The value is [tex]E = 8.9 *10^{-5} \ J[/tex]
Explanation:
From the question we are told that
The area is [tex]A = 0.700 \ m^2[/tex]
The root mean square value is [tex]E_{rms} = 0.0400 \ V/m[/tex]
The time taken is [tex]t = 30.0 \ s[/tex]
Generally the energy is mathematically represented as
[tex]E = c * \sepsilon_o * A * t * E_{rms}^2[/tex]
=> [tex]E = 3.0*10^{8} * 8.85*10^{-12} * 0.700 * 30 * (0.04)^2[/tex]
=> [tex]E = 8.9 *10^{-5} \ J[/tex]
3)What are the "bright stars" that seem to move against the sky? Are they really stars? What are they?
What mirror diameter gives 0.1 arc second resolution for infrared radiation of wavelength 2 micrometers?
Answer:
The diameter of mirror [tex] 5\times10^{-6}\ m[/tex]
Explanation:
Given that,
Wavelength = 2 μm
Resolution = 0.1
We need to calculate the diameter of mirror
Using formula of resolution
[tex]resolution=0.25\times\dfrac{wavelength}{diameter}[/tex]
[tex]diameter =0.25\times\dfrac{wavelength}{resolution}[/tex]
Put the value into the formula
[tex]diameter=0.25\times\dfrac{2\times10^{-6}}{0.1}[/tex]
[tex]diameter = 0.000005\ m[/tex]
[tex]diameter = 5\times10^{-6}\ m[/tex]
Hence, The diameter of mirror [tex] 5\times10^{-6}\ m[/tex]
1. A signal source has an open-circuit voltage of 1V, and a short-circuit current of10mA. What is the source resistance
Answer:
100 Ω
Explanation:
Given that
Open circuit voltage, V = 1 V
Short circuit current, I = 10 mA
Source resistance R, = ?
This is rather a straight forward question. Remember Ohms Law? Current being directly proportional to the voltage and inversely proportional to the resistance?
Yeah, that's the formula we'd be using.
Ohms Law states that V = IR, and thus, if we make R subject of the formula, we have
R = V / I, on substituting the values, we have
R = 1 / 10*10^-3
R = 1 / 0.01
R = 100 Ω
In the Bohr theory of the hydrogen atom, an electron moves in a circular orbit about a proton, assume the radius of the orbit is 5.29 10-11 m.
A) Find the magnitude of the electric force exerted on each particle.B) If this force causes the centripetal acceleration of the electron, what is the speed of the electron?
Answer:
Explanation:
Force between two charged particle having charge q₁ and q₂ at distance r
F = k q₁ x q₂ / r²
Putting the values
F = 9 x 10⁹ x 1.6 x 10⁻¹⁹ x 1.6 x 10⁻¹⁹ / 5.29² x 10⁻²²
= .823 x 10⁻⁷
= 823 x 10⁻¹⁰ N
This force will apply on both the charges and will be attractive in nature .
B )
Let speed of electron be v
centripetal force on electron = F
m v² / r = 823 x 10⁻¹⁰
putting the values for electron
9.1 x 10⁻³¹ x v² / 5.29 x 10⁻¹¹ = 823 x 10⁻¹⁰
v² = 478.42 x 10¹⁰
v = 21.87 x 10⁵ m /s
The work done when a force moves a body through a distance of 15m is 1800j. What is the value of the force applied
Answer:
120
Work :
W = Fd (work = force x distance)
Force :
F = W/d
Distance :
d = W/F
If a space probe moves 20 m in 4 s, how fast is it moving?
Answer:
Speed =distance/time.
=20/4
=5m/s.
Formula: s = d/t
s = speed
d = distance
t = time
Solve using the values we are given.
s = 20/4
s = 5m/s
best of Luck!
[tex]11 \times 4[/tex]
Answer:
44 is right answer
Explanation:
Step 1 :
11+11+11+11+11
step 2:
=22+22
step 3:
=44
hope it helped you:)
Thanks!