The time for which the baseball remains in the air will be 9.37 sec. Option C is correct.
What is the maximum height achieved in projectile motion?It is the height achieved by the body when a body is thrown at the same angle and the body is attaining the projectile motion.
From Newton's first equation of motion;
[tex]\rm v_y= u_y+gt \\\\ 0 = usin \theta - gt \\\\ t = \frac{u sin\theta }{g}\\\\t = 4.68 \ sec[/tex]
The time the baseball remains in the air will be twice the time he travels for one side motion;
T' = 2t
T'=2 × 4.68 sec
T'= 9.37 sec
Hence for 9.37 sec, the baseball willl remains in the air. Option C is correct.
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when energy is transferred from one part of a system to another, some of the energy is lost during the transfer and cannot be used as it was intended. Which two sentences describes examples of this?
Sentences A and D describe examples of energy transformation.Heat is produced when a car's tires rub against the pavement and as electricity passes across power wires, they become hotter.
What is the law of conservation of energy?According to the law of conservation of energy, the energy of an isolated system stays unchanged throughout time.it is said to be conserved.
Energy cannot be created nor destroyed and can be transferred from one form to the other form.
The complete question is
"When energy is moved from one component of a system to another, some of the energy is lost and cannot be used as planned.
Which two statements provide examples?
A. Friction between a car's tires and the road produces heat.
B. Sunlight strikes a solar panel, generating electricity.
c. Stereo speakers emit a sound when powered by electrical energy,
D. Wind moves a turbine, generating electricity.
I E. Power lines heat up as electricity flows through them."
Some of the energy wasted during the movement of energy from one section of a system to another is heat is produced by friction between a car's tires and the road and as electricity passes via power lines, they heat up.
Hence, sentences A and D describe examples of energy transformation.
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Angel hits a ball with a ball. The action is the ball . What what is reaction force?
When Angel hits a ball with the ball. As the action is a ball as it is hitted. The reaction force is the force exerted on another ball.
Newton’s third law of motion describes the two forces, action and reaction forces. This states that for every action force, there is an equal and opposite reaction force.
As Angel hits a ball with another ball, the action is the ball as it is hit. The ball exerts a force on the ball. This is the action force. The ball exerts an equal and opposite force on the bat, which is known as the reaction force.
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Kim is ice-skating going 4.6 m/s. What is her velocity after 10 seconds ?
This is a uniform rectilinear motion (MRU) exercise.
To start solving this exercise, we obtain the following data:
Data:v = 4.6 m/sd = ¿?t = 10 secTo calculate distance, speed is multiplied by time.
We apply the following formula: d = v * t.
We substitute the data in the formula: the speed is equal to 4.6 m/s, the time is equal to 10 s, which is left as follows:
[tex]\bf{d=4.6\dfrac{m}{\not{s}}*10\not{s} }[/tex]
[tex]\bf{d=46 \ m}[/tex]
Therefore, the speed at 10 seconds is 46 meters.
[tex]\huge \red{\boxed{\green{\boxed{\boldsymbol{\purple{Pisces04}}}}}}[/tex]
In which device is chemical energy transformed into electrical energy?
Answer:
A Rechargeable Battery
Explanation:
That is roughly what happens when a secondary cell is recharged (rechargeable battery.) Electric current transforms one chemical species with a lower energy level into another with a higher energy level. When the battery is loaded, this energy can be released. Strictly speaking, no conversion occurs: chemical energy is electrical energy! The energy of electrons in any particular substance, such as metal, are due to electron interactions with the nuclei in the substance and with each other. Electrons, in particular, occupy certain energy levels in metals. Because each metal has a distinct highest occupied energy level, electrons can alter their energies by traveling from one metal to another. An electrical current is made up of this movement!
The frequency of a waveform is found by determining the...
Select one:
a. number of crests passing a point in a given time.
b. distance from a wave's midpoint to its crest.
c. distance between two moving low points of the wave.
d. distance between a crest and a trough.
By counting the number of crests that pass a point in a specific amount of time, one may determine the frequency of a waveform. Option a is correct.
What is the frequency of the sound?A sound pressure wave's frequency, also known as pitch, is the number of times it repeats itself every second.
The frequency of the sound is the inverse of the period. If the wavelength of a wave is short. The wave will indeed have a lower frequency. A longer wavelength denotes a lower frequency.
The frequency of a waveform is found by determining the number of crests passing a point in a given time.
Hence option a is correct.
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An elevator is moving in an upwards direction. The free body diagram for the forces acting on the elevator during this time is: The motion of the elevator can best be described as:
The motion of the elevator can best be described as motion against gravity with negative acceleration.
What is motion?Motion refers to a change in position of an object when it moves from one point another along a reference frame.
An object moving in a downward direction is moving in a positive direction and its velocity increases relative to the earth since gravity acts downwards.
An object moving in a upward direction is moving in a negative direction and its velocity decreases relative to the earth since gravity acts downwards.
Therefore, the motion of the elevator can best be described as motion against gravity with negative acceleration.
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(The question and setup are below)
The gauge pressure at bottom of vaccine solution will be 16 kPa
Positive pressure is another name for gauge pressure. When a system's internal pressure exceeds that of its surroundings, it is said to be under positive pressure. Any leak that develops in the positively pressured system will therefore escape into the outside world. In contrast, a negative pressure chamber draws air into it.
Given As seen in the illustration, a syringe is held vertically. The container carries a 3 cm tall column of vaccine solution and has an open inner diameter of 1 cm. The needle contains a 2 cm column of vaccine solution and has an open inner diameter of 0.5 mm. At the needle's open end, the solution is exposed to the air. The vaccination solution has a density of 1200 kg/m3.
We have to find the gauge pressure at bottom of vaccine solution
Since the 5N force is applied to vaccine solution the pressure exerted will be much more
Hence the gauge pressure at bottom of vaccine solution will be 16 kPa
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In the image below, a worker is pushing a crate with a mass of 10 kg up a
ramp at a constant rate. Ignoring friction, how much force must the worker
apply so that the crate continues to move at the same speed? (Recall that g =
9.8 m/s²)
A. 25.6 N
B. 67.5 N
C. 16.2 N
D. 49.0 N
Answer:
D. 49N
Explanation:
Because there is no acceleration the sum of the forces in the x-direction is zero. Your weight force is mass x gravity which is 98N. The x-component of which is sin(30). 98sin30 = 49N in the negative x-direction. -49N + The force applied by the worker must equal zero. So, the force applied by the worker must be 49N.
What is temperature?
A. A type of heat transfer
ANUN
B. The measure of an object's "hotness"
APATIN
HERRE
C. Electromagnetic waves
Digita
D. The energy transferred between objects
H
The term temperature has to do with the measure of an object's "hotness".
What is temperature?The term temperature has to do with how hot or cold a body is. In other words, the word temperature brings us to call to mind the degree of hotness or coldness of a body.
Succinctly put, the term temperature has to do with the measure of an object's "hotness".
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One endpoint of a line segment is (1, 2) and the midpoint of the line segment is
(−1, 4). What is the other endpoint?
It then can be stated:
[tex]\large\red\hookrightarrow \rm \large \: \:X_m \: = \: \frac{X_1 \: + \: \: X_2 }{2} \: \: \: \: \: \: \: \:... (1) \\ [/tex]
[tex]\large\red\hookrightarrow \rm \large \: \:Y_m \: = \: \frac{Y_1 \: + \: \: Y_2 }{2} \: \: \: \: \: \: \: \:... (2)\\ [/tex]
Since, Xm = -1 and X1 = 1 we can write equation (1) as
[tex]\large\purple\longrightarrow \rm \large \: \:-1 \: = \: \frac{1 \: + \: \: X_2 }{2} \: \: \: \: \: \: \: \:... (1) \\ [/tex]
[tex]\large\purple\longrightarrow \rm \large \: \:-2 \: = \:1 \: + \: X_2[/tex]
[tex]\large\purple\longrightarrow \rm \large \: \: - 2 \: - 1 \: = \: X_2[/tex]
[tex]\large\purple\longrightarrow \rm \large \: \: - 3 \: = \: X_2[/tex]
Since , Ym = 4 and Y1 = 2 we can write the equation (2) as
[tex]\large\purple\longrightarrow \rm \large \: \:4 \: = \: \frac{2 \: + \: \: Y_2 }{2} \: \: \: \: \: \: \: \:... (2)\\ [/tex]
[tex]\large\purple\longrightarrow \rm \large \: \:8 \: = \: 2 \: + \: Y_2[/tex]
[tex]\large\purple\longrightarrow \rm \large \: \:8 \: - \: 2 \: = \: Y_2[/tex]
[tex]\large\purple\longrightarrow \rm \large \: \:6 \: = \: Y_2[/tex]
Therefore the other endpoint of the line (X2, Y2) is (-3 , 6)
A small mass m slides with negligible friction down an incline at an angle of 25.76° with respect to the horizontal. It then drops down to a horizontal surface and bounces elastically back up as shown.
The picture is to scale. It shows the position of the mass at equal time intervals starting from rest at T. The height of the mass at X is the same as at V. Click here to view the motion of the mass m.
(options are: less than, greater than, equal to)
• The speed change between T and S is (blank) between S and R.
• The speed of m at X is (blank) that at Q.
• The size of the total force on m at P is (blank) at U.
• The mechanical energy of m at P is (blank) that at V.
• The size of the total force on m at S is (blank) at P.
• The velocity of m at X is (blank) that at V.
• The speed change between T and S is greater between S and R.
• The speed of m at X is greater that at Q.
• The size of the total force on m at P is less at U.
• The mechanical energy of m at P is equal to that at V.
• The size of the total force on m at S is greater at P.
• The velocity of m at X is equal to that at V.
What is mechanical energy?The mechanical energy is the sum of kinetic energy and the potential energy of an object at any instant of time.
M.E = KE +PE
Given is a small mass m slides with negligible friction down an incline at an angle of 25.76° with respect to the horizontal. It then drops down to a horizontal surface and bounces elastically back up as shown.
The picture shows the position of the mass at equal time intervals starting from rest at T. The height of the mass at X is the same as at V.
Between T to S and S to R, the mass is under constant acceleration. Time taken to move from T to S is greater than S to R. Thus, the speed change between T and S is greater than between S and R.
At Q, there is only a horizontal velocity component, but at X. the speed will be greater and has both vertical and horizontal component. Thus, the speed of m at X is greater than that at Q.
Force is given as the rate of change of momentum with time. At U, change in momentum is large compared to P. Thus, the size of the total force on m at P is less at U.
There is no friction acting on the system. So the energy remains conserved. Mechanical energy at P = V.
The force on mass m at S is only the gravity force. The remaining forces are cancelled by the normal force. Thus, size of the total force on m at S is greater at P.
The energy is conserved at each point of motion of mass. If X and V are at same height, they have same potential energy and so their kinetic energy. Thus, velocity of m at X is equal to that at V.
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what’s better csp or pv ?
Answer:
CSP
Explanation:
CSP systems store energy through Thermal Energy Storage technologies (TES), so power can be used when there isn't enough sunlight. PV systems, however, can't store thermal energy because they use direct sunlight, rather than heat. For this reason, CSP systems are better for energy storage and efficiency.
PLEASE HELP!! 50 points. The answer is not 2.6 m/s.
Answer:
A
Explanation:
5.2mm/s
hope this helps
Consider an imaginary cylinder with a radius of r = 0.185 m and a length of l = 0.440 m that has an infinite line of positive charge running along its axis. The charge per unit length on the line is λ = 4.50 μC/m.
1.What is the electric flux through the cylinder due to this infinite line of charge?
2.What is the flux through the cylinder if its radius is increased to r= 0.600 m ?
3.What is the flux through the cylinder if its length is increased to l= 0.990 m ?
The electric flux through the cylinder due to this infinte line is 1 355 x 10' N m²/C, The electric flux through the cylinder is independent of the radius of the cylinder. So, the electric flux through the cylinder is the same as in part (a) which is equal to is 1.355 10 Nm C and The electric flux through the cylinder due to this infinte line is 2.711 x 10' N m² C
Given an imaginary cylinder with a radius of r = 0.185 m and a length of l = 0.440 m that has an infinite line of positive charge running along its axis. The charge per unit length on the line is λ = 4.50 μC/m.
Solve for the electric flux through the cylinder due to this infinte line:
As below equation mentions, the electric flux for a uniform electric filed is given by:
Фₓ = EA cosΦ
Φₓ = λLcosΦ)/ε
Φₓ = (3 x 10^(-6) x 0.4 x cos0)/(8.854 x 10^(-12))
Φₓ = 1.355 x 10^(5) Nm²/C
Hence the electric flux through the cylinder due to this infinte line is 1 355 x 10' N m²/C, The electric flux through the cylinder is independent of the radius of the cylinder. So, the electric flux through the cylinder is the same as in part (a) which is equal to is 1.355 10 Nm C and The electric flux through the cylinder due to this infinte line is 2.711 x 10' N m² C
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A car moves with the speed of 40km/hr for the first half distance and 60km/hr for second half distance.find average speed of car?
Answer:
50km/h
Explanation:
average = (a + b) / 2
average = (60 + 40) / 2
average = 50
how do I calculate equilibrant and fx and fy. I don't understand what they are asking
(a) The equilibrant C for force of vector A and B is 3.43 N.
(b) The equilibrant C for fx of vector A and B is 2.1 N.
(c) The equilibrant C, for fy of vector A and B is 2.12 N.
What is equilibrant force?An equilibrant force is a single force that will bring other bodies into equilibrium.
From configuration 1:Vector A: mass = 0.2 kg, θ = 20⁰
Vector B: mass = 0.15 kg, θ = 80⁰
Fx = mg cosθ
Fy = mg sinθ
where;
m is mass g is acceleration due to gravityVector AForce of A due to its weight
F(A) = mg
F(A) = 0.2 x 9.8 = 1.96 N
Fx = (0.2 x 9.8) cos(20) = 1.84 N
Fy = (0.2 x 9.8) sin(20) = 0.67 N
Resultant forceR = √(0.67² + 1.84²)
R = 1.96 N
Vector BForce of B due to its weight
F(B) = mg
F(B) = 0.15 x 9.8
F(B) = 1.47 N
Fx = (0.15 x 9.8) cos(80) = 0.26 N
Fy = (0.15 x 9.8) sin(80) = 1.45 N
Resultant forceR = √(0.26² + 1.45²)
R= 1.47 N
Equilibrant C of vector A and BEquilibrant force:
Force, C = 1.96 N + 1.47 N
Force, C = 3.43 N
Equilibrant FX:
Fx, C = Fx(A) + Fx(B)
Fx, C = 1.84 N + 0.26 N = 2.1 N
Equilibrant FY:
Fy, C = Fy(A) + Fy(B)
Fy, C =0.67 N + 1.45 N = 2.12 N
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A circular wheel of mass 50 kg and radius 200 mm is rotating at 300 r.p.m. Find its kinetic energy.
yhisriyftt
carzy and want one g come 6x 10-1'coulomb or one unit. The ratio, mass for each of the particle is 9.58 x 10" per gram. Hence, the mass
If the mass of the falling object is 60kg. Calculate force. [Take g=10m/s2]
Put the steps of the scientific method in order.
A. Question -> Research -> Hypothesis -> Experiment -> Analysis -> Conclusion
B. Research -> Hypothesis -> Experiment ->Question -> Conclusion -> Analysis
C. Research -> Question -> Hypothesis -> Experiment -> Analysis -> Conclusion
D. Hypothesis -> Experiment -> Conclusion -> Question -> Research -> Analysis
Answer:
c
Explanation:
Answer:
c
Explanation:
im smart
Estimate the gravitational force of attraction between two people sitting side by side on a park bench. How does this force compare with the gravitational force exerted on each of them by the Earth
Weight is compared with the gravitational force exerted on each of them by the Earth.
What is Newton's law of gravitation?Newton's law of gravity states that each particle having mass in the universe attracts each other particle with a force known as the gravitational force.
The gravitational force is proportional to the product of the masses of the two bodies and inversely proportional to the square of their distance.
When mass increases and distance reduces, gravity rises. Gravity also lowers when the distance between two points grows and the mass decreases.
The gravitational force is balanced by weight;
[tex]\rm F = W \\\\ G\frac{mM}{r^2} =mg[/tex]
Hence, weight is compared with the gravitational force exerted on each of them by the Earth.
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A squirrel sitting on the ground starts to run with an acceleration of 5.1 m/s².
How fast is the squirrel going after 0.25 seconds?
O A. 20.4m/s
OB. 0.49 m/s
OC. 3.1 m/s
OD. 1.28 m/s
Answer:
0.159
Explanation:
the formula to find its is 1÷2*gt^2
Answer:
D
Explanation:
v= a t
= 5.1 * .25 = 1.275 m/s
Answer asap for brainlist
They use less wire, A
Wavelength is determined by dividing a wave's speed by its frequency. If a wave has a frequency of 1 hertz and a speed of 20 m/s, what is its wavelength?
Select one:
a. 80 m
b. 5 m
c. 0.05 m
d. 20 m
Answer:
D. 20m
Explanation:
this answer is 20 m.
wavelength = velocity / frequency
A truck accelerating at 0.0083 meters/second2 covers a distance of 5.8 × 104 meters. If the truck's mass is 7,000 kilograms, what is the work done to reach this distance?
Answer:
Explanation:
Force:
⇒ Mass × Acceleration
Work Done:
⇒ Force × Distance
Calculations:
⇒ Force = 0.0083 × 7000 N
⇒ Work done = 0.0083 × 7000 × 5.8 × 10^4 Joules
Why is a valve placed before the rotameter?
a.To measure the flow of liquid entering the extraction bed
b.To regulate the flow of fluid leaving the extraction bed
c.To regulate the flow of liquid entering the extraction bed
d.None of the above.
A valve placed is before the rotameter to regulate the flow of liquid entering the extraction bed. The correct option is c.
What is control valve?Control valves are generally used to maintain a flow as close as possible to the desired value.
Valves positioned before the rotameter for throttling purposes. A control valve will regulates the rate of fluid flow. Control valves control typically flow rate, pressure, and temperature.
Thus, the correct option is c.
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Calculate the approximate number of atoms in a bacterium, assuming the average mass of an atom is ten times the mass of a hydrogen atom. The mass of a bacterium is 10−15 kg and the mass of a hydrogen atom is of the order of 10−27 kg.
atoms
10¹¹ is the approximate number of atoms in a bacterium.
What do you understand by mass of element?
The atomic mass of an element is the average mass of the atoms of an element measured in atomic mass unit (amu).
Given,
Mass of a bacterium atom = 10⁻¹⁵ kg.
Mass of a hydrogen atom = 10⁻²⁷ kg.
From the above observation ,
The average mass of an atom of the bacterium is ten times the mass of a hydrogen atom.
Atomic mass 1 bacterium atom = 10 x mass of hydrogen atom
= 10 x 10⁻²⁷ kg.
= 10⁻²⁶ kg.
Thus,
The number of atoms in a bacterium
= [tex]\frac{Total mass}{Atomicmass of 1 bacterium}[/tex]
= [tex]\frac{10^{-15} }{10^{-26} }[/tex]
= [tex]10^{11}[/tex]
The approximate number of atoms in a bacterium is [tex]10^{11}[/tex].
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A satellite completes one revolution of a planet in almost exactly one hour. At the end of one hour, the satellite has traveled 2.0 × 107 meters and is only 10 meters away from its starting point. What is the numerical value of the satellite's average velocity after that one hour?
Answer:
shown below
Explanation:
2 x 10⁷ as a number is 20,000,000
20,000,000 - 10 = 19,999,990
It went 19,999,990 m/h
in km/h:
19,999,990 / 1000 = 19,999.99 km/h
in km/s
19,999,990 / 3,600,000 = ~5.56 km/s
in m/s
19,999,990 / 3600 = ~5555.56 m/s
state how the centripetal force is provided in a c held on a playground roundabout
The centripetal force is obtained by its formulas is,[tex]\rm F_C= \frac{mv^2}{r}[/tex]
What is centripetal acceleration?The acceleration needed to move a body in a curved way is understood as centripetal acceleration.
The direction of centripetal acceleration is always in the path of the center of the course. The total acceleration is the result of tangential and centripetal acceleration.
The formula for the centripetal force is ;
[tex]\rm F_C= \frac{mv^2}{r}[/tex]
Where,
r is the radius
v is the linear speed
m is the mass of an object
Hence, the centripetal force obtained by its formulas as,[tex]\rm F_C= \frac{mv^2}{r}[/tex]
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The half-life of Iodine-131 is 8.0252 days. If 14.2 grams of I-131 is released in Japan and takes 31.8 days to travel across the Pacific, how much I-131 will be left by the time it reaches California?
Answer:
Explanation:
Half-life problems are modeled as exponential equations. The half-life formula is [tex]P=P_o\left (\dfrac{1}{2} \right)^{\frac{t}{k}}[/tex] where [tex]P_o[/tex] is the initial amount, [tex]k[/tex] is the length of the half-life, [tex]t[/tex] is the amount of time that has elapsed since the initial measurement was taken, and [tex]P[/tex] is the amount that remains at time [tex]t[/tex].
[tex]P=14.2\left (\dfrac{1}{2} \right)^{\frac{t}{8.0252}}[/tex]
Deriving the half-life formula
If one forgets the half-life formula, one can derive an equivalent equation by recalling the basic an exponential equation, [tex]y=a b^{t}[/tex], where [tex]t[/tex] is still the amount of time, and [tex]y[/tex] is the amount remaining at time [tex]t[/tex]. The constants a and b can be solved for as follows:
Knowing that amount initially is 14.2g, we let this be time zero:
[tex]y=a b^{t}[/tex]
[tex](14.2)=ab^{(0)}[/tex]
[tex]14.2=a *1[/tex]
[tex]14.2=a[/tex]
So, [tex]a=14.2[/tex], which represents out initial amount of the substance, and our equation becomes: [tex]y=14.2 b^{t}[/tex]
Knowing that the "half-life" is 8.0252 days (note that the unit here is "days", so times for all future uses of this equation must be in "days"), we know that the amount remaining after that time will be one-half of what we started with:
[tex]\left(\frac{1}{2} *14.2 \right)=14.2 b^{(8.0252)}[/tex]
[tex]\dfrac{7.1}{14.2}=\dfrac{14.2 b^{8.0252}}{14.2}[/tex]
[tex]0.5=b^{8.0252}[/tex]
[tex]\sqrt[8.0252]{\frac{1}{2}}=\sqrt[8.0252]{b^{8.0252}}[/tex]
[tex]\sqrt[8.0252]{\frac{1}{2}}=b[/tex]
Recalling exponent properties, one could find that [tex]\left ( \frac{1}{2} \right )^{\frac{1}{8.0252}}=b[/tex], which will give the equation identical to the half-life formula. However, recalling this trivia about exponent properties is not necessary to solve this problem. One can just evaluate the radical in a calculator:
[tex]b=0.9172535661...[/tex]
Using this decimal approximation has advantages (don't have to remember the half-life formula & don't have to remember as many exponent properties), but one minor disadvantage (need to keep more decimal places to reduce rounding error).
So, our general equation derived from the basic exponential function is:
[tex]y=14.2* (0.9172535661)^t[/tex] or [tex]y=14.2*(0.5)^{\frac{t}{8.0252}}[/tex] where y represents the amount remaining at time t.
Solving for the amount remaining
With the equation set up, substitute the amount of time it takes to cross the Pacific to solve for the amount remaining:
[tex]y=14.2* (0.9172535661)^{(31.8)}[/tex] [tex]y=14.2*(0.5)^{\frac{(31.8)}{8.0252}}[/tex]
[tex]y=14.2* 0.0641450581[/tex] [tex]y=14.2*(0.5)^{3.962518068}[/tex]
[tex]y=0.9108598257[/tex] [tex]y=14.2* 0.0641450581[/tex]
[tex]y=0.9108598257[/tex]
Since both the initial amount of Iodine, and the amount of time were given to 3 significant figures, the amount remaining after 31.8days is 0.911g.