Answer: 5 years
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = x
a - x = amount left after decay process = [tex]\frac{x}{16}[/tex]
a) for calculating k
[tex]20=\frac{2.303}{k}\log\frac{x}{\frac{x}{16}}[/tex]
[tex]k=\frac{2.303}{20}\log{16}[/tex]
[tex]k=0.138years^{-1}[/tex]
b) for calculating half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{0.138years^{-1}}[/tex]
[tex]t_{\frac{1}{2}}=5years[/tex]
Thus its half life is 5 years
State the name of the process in each of the following changes of state:
a) Solid to a liquid
b) Liquid to a solid
c) Gas to a liquid
d) Liquid to a gas
Answer:
A. Melting
B. Freezing
C. Condensing
D. Boiling
Explanation:
What is the critical angle for glass when the refractive index is 1.45
Answer:43.6°
Explanation:
Refractive index=n=1.45
Critical angle=c
n=1/sinc
1.45=1/sinc
Cross multiply
1.45sinc=1
Divide both sides by 1.45
(1.45sinc)/1.45=1/1.45
sinc=0.6897
c=sin(inverse)(0.6897)
c=43.6°
Critical angle is 43.6°
Object A has a mass of 10 kg and is moving at a velocity of 2.0
m/s. So Object A's momentum is - kg. m/s.
Answer:20kgm/s
Explanation:
Mass=10kg
Velocity=2m/s
Momentum=mass x velocity
Momentum=10 x 2
Momentum=20
Momentum=20kgm/s
The object with mass m when moving with the velocity, its momentum can be calculated. The momentum of the object A is 20 kg.m/s.
What is momentum?Momentum is the product of mass and velocity of a moving object.
If the momentum is p, the mass of the object is 10 kg and the velocity is 2.0 m/s, then the momentum will be
p = 10 × 2.0
p = 20 kg.m/s
Thus, the momentum of the object A is 20 kg.m/s
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A light ray has an angle of incidence of 34º. The reflected ray will make what angle with the reflecting surface?
Answer:
Angle of incidence = Angle of Reflection
34° = Angle of Reflection
So, Angle of Reflection is equal to 34°
hope it helps!
Answer: 56 degrees
Explanation:
The angle of incidence is equal to the angle of reflection, but it is not asking us for the angle of reflection. It is asking us for the angle with the reflected SURFACE. It is 90-34= 56. Look at the pic attached if you need a labelled diagram
Determine the magnetic flux through a square loop of side a if one side is parallel to, and a distance b from a straight wire that carries a current I.
1. If the loop is pulled away from the wire at speed v, what emf is induced in it?
2. Which way does the induced current flow through the loop?
3. How does the emf vary in time, if the initial position of the left vertical side was b0 at time t=0?
4. Determine the force F required to pull the loop away from the line of current.
Answer:
Find the given attachments
The measured mass of a body is found to be 110g. The length is measured by a meter scale. Actual mass and length of the body are 100 g and 10 cm. Find the percentage error in the calculation of density.
Answer:
ok it will be g+181
Explanation:
Need help on circuit question
When using the lens equation, a negative value as the solution for d baseline i indicates that the image is
A. real
B. virtual
C. upright
D. inverted
When using the lens equation, a negative value as the solution for d baseline i indicates that the image is Virtual. The correct option is B.
What is reflection?When a light strikes on a shiny surface, it reflects back the light ray in the same medium. The phenomenon is called reflection and the ray is called the reflected ray.
From the Len's maker formula, e have
1/f = 1/u + 1/v
where f = radius of curvature /2
So, the negative value as the solution for d baseline i indicates that the image is Virtual.
Thus, the correct option is B.
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A balance between gravity and bouyancy is called
Answer:
I believe it is isostasy
Explanation:
(x) A change in position is called:
(a) Speed
(b) velocity
(c) displacement
(d) distance
Answer:
(c) displacement
sure answer...
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Which equation is used to calculate the magnetic force on a charge moving in a magnetic field?
F = |g|vBcose
F = |g|vBsine
F = 1g|Bcose
F = 1g|Bsine
Answer:
B
Explanation:
I don’t know where each one goes
what are the dimensions of the rectangle
Answer:
A rectangle has two dimensions:we can measure its length and,perpendicular to that,its width.
Explanation:
A 1 kg ball is rolling at 3 m/s.
Answer:
It will roll 9 meters in 3 seconds
Explanation:
3 m/s times 3 is 9
Thanks for warning me.
I'll be careful to stay out of its way.
Do you have a question to ask ?
A Nichrome (TM) wire has a resistance of 100.00 Ω at 11.5ºC. What is the resistance of at 10.0ºC ? The temperature coefficient of resistivity for Nichrome (TM) is 0.00040 (Cº)^-1.
A spherical mirror has a radius of curvature of -14 cm. What type of mirror could it be?
Answer:99.9 ohm
Explanation:
Refer to the model below. A science student is camping with her family for one month at Stone Mountain Park. In a journal she records a model of the moon phases she observes. If she began recording the moon phases at position X, which sequence of Moon phase models could be seen by her during the 4-week period?
Answer:
New Moon - Crescent Moom ---- Full Moon ---- Waning Quarter
Explanation:
The Moon revolves around the Earth in a 28 day period, which is approximately one Earth month, therefore S the student has been recording the movement of the Moon for 4 Earth weeks this is a period of complete revolution of the Moon .
Consequently you must register the following phases
New Moon - Crescent Moom ---- Full Moon ---- Waning Quarter
in the period where it begins, it must go through the cycle in an orderly way to the right.
Do u think the benefits of nuclear energy outweigh the dangers
Answer:
While there is no such thing as 100 percent safe, having nuclear energy is much safer than you think. It's thousands of times safer than conventional coal and other fossil-fuel-derived energy, not to mention the specter of environmental disaster from continued use of carbon-based energy sources.29 may. 2011
Explanation:
I hope it helps you
Some drops a ball off of the top of a 125-m-tall building. In this prob-lem, you will be solving for the time it takes the ball to hit the ground.(a)Define your coordinate system, be thorough.(b)Write down the given infor-mation, be sure to include hidden information.(c)State what physics principleis at play here. How do you know this?(d)Select an equation.(e)Solve forthe time it takes for the ball to hit the ground.
Answer:
t = 5.05 s
Explanation:
This is a kinetic problem.
a) to solve it we must fix a reference system, let's use a fixed system on the floor where the height is 0 m
b) in this system the equations of motion are
y = v₀ t + ½ g t²
where v₀ is the initial velocity that is v₀ = 0 and g is the acceleration of gravity that always points towards the center of the Earth
e) y = 0 + ½ g t²
t = √ (2y / g)
t = √(2 125 / 9.8)
t = 5.05 s
El coeficiente de variación de la resistencia con la temperatura del carbón es -0.0005/°c.Si la resistencia de una resistencia de carbón es de 1000 a0°c , determine su resistencia a 120°c
Answer:
R (120) = 940Ω
Explanation:
The variation in resistance with temperature is linear in metals
ΔR (T) = R₀ α ΔT
where α is the coefficient of variation of resistance with temperature, in this case α = -0,0005 / ºC
let's calculate
ΔR = 1000 (-0,0005) (120-0)
ΔR = -60 Ω
ΔR = R (120) + R (0) = -60
R (120) = -60 + R (0)
R (120) = -60 + 1000
R (120) = 940Ω
How do I write answers in standard form?
Answer:
Example
Write 81 900 000 000 000 in standard form: 81 900 000 000 000 = 8.19 × 1013
It’s 1013 because the decimal point has been moved 13 places to the left to get the number to be 8.19
How do most fossils form? Be sure to explain your
answer
I
Intro
Here your answer
Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.
hope it helps ☺️✌️
Answer:
over years of being underground the pressure causes the organism to press into the rock and form a mold. this mold is the fossil and are found in sedimentary rock
Calculate the first and second velocities of the car with four washers attached to the pulley, using the formulas
v1 = 0.25 m / t1 , and v2 = 0.25 m / (t2 – t1)
where t1 and t2 are the average times the car took to reach the 0.25 and the 0.50 meter marks. Record these velocities, to two decimal places, in Table E
The first and second velocities of the car, with four washers attached to the pulley, are both 0.125 m/s.
We must apply the following calculations to determine the car's first and second velocities with the four washers attached to the pulley:
v1 = 0.25 m / t1
v2 = 0.25 m / (t2 - t1)
Here, t1 denotes the typical time needed for the car to go 0.25 metres, and t2 is the typical time needed to travel 0.50 metres.Let's say that t1 and t2 are the typical times, each lasting two seconds on average.The first formula allows us to determine v1:
v1 = 0.25 m / 2 s = 0.125 m/s
Using the second formula, we can calculate v2:
v2 = 0.25 m / (4 s - 2 s) = 0.125 m/s
Table E can be used to record these values as the velocities at the relevant distances.
for such more questions on velocities
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Help
What are energy and work
Answer:
In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed.
In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed.
Explanation:
HOPE THIS HELPSGamma radiation is...
An electromagnetic wave
Safe
A helium nucleus
An electron
Answer:
A. Gamma radiation is an electromagnetic wave.
Explanation:
" Gamma ray is an electromagnetic radiation from a nucleus. It is not safe.
" Nucleus of a helium atom is called Alpha particle.
..
Hope this answer can help you,
Uranium-235 has 92 protons. How many neutrons does it have?
Answer:
146 neutrons.
Explanation:
plzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz mark me brainliest
Answer: The atomic number of uranium (see periodic table) is 92, and the mass number of the isotope is given as 238. Therefore, it has 92 protons, 92 electrons, and 238 — 92 : 146 neutrons.
Explanation:
how do you convert a negative charge to a positive charge?
Answer:
Add the negative protons, to make a positive charge. It's just like math a double negative makes a positive.
~Mia Sedillo~You have a large flashlight that takes 4 D-cell batteries, each with a voltage of 1.5 volts. If the current in the flashlight is 2.0 amps, what is the
resistance?
A 12 ohms
B 0.75 ohms
C 3.0 ohms
D.0.5 ohms
E. 6.0 ohms
Answer:
The answer is "C. 3.0 ohms".
Explanation:
Ohm's law states the following:,
V = IR
where:
Voltage (V) = 1.5 volts × 4 batteries = 6.0 volts
Current (I) = 2.0 amps
Resistance (R) = ? ohms
To solve for Resistance (R) the equation must be rearranged this way:
R = V / I
Then, the variables must be replaced with the known values:
R = 6.0 volts / 2.0 amp
R = 3.0 ohms
The answer is C. 3.0 ohms.
------------
P.D: I got it right on PLATO
2. A disturbance that generates a wave may be a simple pulse or shock.
b. False
a.
True
That's true.
-- a bell starts ringing (wave) when you tap it (simple pulse)
-- a pond starts rippling (wave) when a stone drops in (simple shock)
-- a guitar strings starts waving when you pluck it
A trip is taken that passes through the following points in order
Point A 0 m
Point B 15.0 m
Point C -30.0 m
Point D -20.0 m
Point E 10.0 m
Point F 5.0 m
What is the distance from Point C to Point E?
answers :
20.0 m
40.0 m
-20.0 m
10.0 m
Answer:
40.0 m
...............
Answer:
35
Explanation:
Which biome contains mostly coniferous trees and receives 35 to 100 cm of rain per year?
The question is incomplete as it does not have the options which are:
deciduous forest
taiga (boreal forest)
temperate rainforest
tropical rainforest
Answer:
Taiga (boreal forest)
Explanation:
A Biome refers to the habitat which is occupied by flora and fauna living in similar conditions. These biomes are distinguished based on many features like precipitation, temperature and many other physical factors.
In the given question, the biome which receives an annual rainfall of 35 to 100 cm annually and is mostly covered by the coniferous trees is known as "Taiga biome" which is also known as Boreal forest.
The Taiga biome is one of the largest terrestrial biomes which is present in Eurasia and North America. The biome is characterised by the conifers trees and therefore is also known as the Coniferous trees.
Thus, Taiga (boreal forest) is the correct answer.
Answer: Taiga(boreal forest)
Explanation:
