Answer:
I. 100 Bg
II. 50 Bg
III. 25 Bg
Explanation:
I. Determination of the activity after 26 hours.
We'll begin by calculating the number of half-lives that has elapse. This can be obtained as follow:
Half-life (t½) = 13 hours
Time (t) = 26 hours
Number of half-lives (n) =?
n = t / t½
n = 26 / 13
n = 2
Finally, we shall determine remaining activity
Original activity (N₀) = 400 Bg
Number of half-lives (n) = 2
Activity remaining (N) =?
N = 1/2ⁿ × N₀
N = 1/2² × 400
N = 1/4 × 400
N = 100 Bg
II. Determination of the activity after 39 hours.
We'll begin by calculating the number of half-lives that has elapse. This can be obtained as follow:
Half-life (t½) = 13 hours
Time (t) = 39 hours
Number of half-lives (n) =?
n = t / t½
n = 39 / 13
n = 3
Finally, we shall determine remaining activity.
Original activity (N₀) = 400 Bg
Number of half-lives (n) = 3
Activity remaining (N) =?
N = 1/2ⁿ × N₀
N = 1/2³ × 400
N = 1/8 × 400
N = 50 Bg
III. Determination of the activity after 52 hours.
We'll begin by calculating the number of half-lives that has elapse. This can be obtained as follow:
Half-life (t½) = 13 hours
Time (t) = 52 hours
Number of half-lives (n) =?
n = t / t½
n = 52 / 13
n = 4
Finally, we shall determine remaining activity
Original activity (N₀) = 400 Bg
Number of half-lives (n) = 4
Activity remaining (N) =?
N = 1/2ⁿ × N₀
N = 1/2⁴ × 400
N = 1/16 × 400
N = 25 Bg
Write an article to explain the process that occurs when matter is heated, or cooled. How does matter change its physical state between solid, liquid, and gas? Provide a real-life example. Also, describe the properties of the three main states of matter.
Answer:
when matter is heated or cooled it melts or freezes for at least the atoms do
Explanation:
for example take water when you heat it up the water molecules melt producing vapor water vapor and when you freeze it or cool it down it turns into liquid or turned into a solid by turning into ice. the three main properties of matter are gas liquid and solid and if we put water into these three different categories it turns into water vapor as gas liquid water as liquid and Ice as a solid
hope this helps
What is the maximum centripetal acceleration experienced by a person standing still on the surface of the Earth? Where must they be located?
Answer:
The person must be located in the Equator Line. The maximum centripetal acceleration experienced by a person is 0.0337 meters per square second.
Explanation:
Physically speaking, the centripetal acceleration ([tex]a_{r}[/tex]), measured in meters per square second, experienced by a person is defined by the following expression:
[tex]a_{r} = \omega^{2}\cdot r[/tex] (1)
Where:
[tex]\omega[/tex] - Angular speed of the Earth, measured in radians per second.
[tex]r[/tex] - Distance perpendicular to the rotation axis, measured in meters.
Since rotation axis passes through poles and distance described above is directly proportional to centripetal acceleration. The person must be located in the Equator Line, which is equivalent to the radius of the planet.
In addition, the angular speed of the Earth can be calculated in terms of its period ([tex]T[/tex]), measured in seconds:
[tex]\omega = \frac{2\pi}{T}[/tex] (2)
If we know that [tex]r = 6.371\times 10^{6}\,m[/tex] and [tex]T = 86400\,s[/tex], then the maximum centripetal acceleration experienced by a person is:
[tex]a_{r} = \left(\frac{2\pi}{86400\,s} \right)^{2}\cdot (6.371\times 10^{6}\,m)[/tex]
[tex]a_{r} = 0.0337\,\frac{m}{s^{2}}[/tex]
The maximum centripetal acceleration experienced by a person is 0.0337 meters per square second.
The person standing still on the surface of the earth must be located in the equator line
Recall: the the centripetal acceleration at the Equator is about 0.03 m/s2.
This then means that the maximum centripetal acceleration of a person standing in the equator line is 0.03 m/s2
What is meant by maximum centripetal acceleration?The maximum centripetal acceleration as the name implies is the maximum speed of a body or object in a circular path
Learn more about centripetal acceleration:
https://brainly.com/question/25243603
A 2[kg] rock and a 4[kg] rock are lifted to a height of 10[m].
How much PE does each rock have?
Answer:
See below
Explanation:
Potential Energy = mgh
for 2 rock = 2 * 9.81 * 10 = 196.2 j
for 4 rock = 4 * 9.81 * 10 = 392.4 j
Name the nutrients required for the body
Answer:
Explanation:
Water.
Carbohydrates.
Protein-Amino acids.
Fat.
Vitamins.
Minerals.
Omega-3 fatty acids.
Q:- EXPLAIN WHY THE PLANETS DO NOT TWINKLE.
planets shine more stedily because they are closer to earth and so appear as pinpoints but as tiny disks in our sky.
Why is the total solar eclipse important for scientists? explain
Answer:
hello
Explanation:
For scientists, they offer a unique opportunity to study aspects of the sun like its corona, the layer of plasma surrounding the star. ... By studying the inner regions of the corona that we can generally only see and photograph well during a total solar eclipse, scientists can learn more about how weather works in space.
have a nice day
hope it helps
byee
Answer:
For scientists,they offer a unique opportunity to study aspects of the sun like it's Corona, the layer of plasma surrounding the star......By studying the inner regions of the Corona that we can generally only see and photograph well during a total solar eclipse, scientists can learn more about how weather works in space
A meteorologist who has been analyzing weather data from the last fifty years found evidence of climate change. An ecologist has been studying deposits of pollen from the last fifty years to track the types of plants that grew in certain regions. She has also found evidence of climate change. What does this imply about science?
A. Meteorology and ecology are the same type of science.
B. When scientific disciplines overlap, researchers should choose new topics.
C. Different scientific disciplines can be used to investigate similar questions.
D. There should be fewer sciences, as they seem to answer the same questions.
Explain
Answer:
Probably (C), but don't forget the argument that:
Roses are red, and roses are flowers; therefore all flowers are red.
What are the properties of fourth matter plasma?
[tex] \\ [/tex]
Like gases, plasmas have no fixed shape or volume, and are less dense than solids or liquids. But unlike ordinary gases, plasmas are made up of atoms in which some or all of the electrons have been stripped away and positively charged nuclei, called ions, roam freely.
[tex] \\ [/tex]
Hope It Helps!
walking dancing and even some household chores are?
Answer:
Actions
Explanation:
if u mean what are these called then it's actions
Answer: Regular Physical Activity
Explanation:
The Sun is spherical due to
gravitation
Earth and Moon circling it.
Earth circling it.
none of the above
Answer:
gravitation
good luck, hope this helps :)
What is the correct description of any change in a position farther to the left of zero?
1- negative displacement
2- negative position
Answer:
negative displacement
Explanation:
cause its written farther that means its doin movement
your "A" never changes, while your "Y" changes depending on strength of gravity. is it mass or weight?
Answer:
A - mass. B - Weight
Explanation:
This is because weight varies with the strength of gravity. Mass is just the amount of matter in an object
Two long parallel wires 20 cm apart carry currents of 5.0 A and 8.0 A in the between the two wires where the magnetic field is zero?
a. yes, midway between the wires
b. yes, 12 cm from the 5-A wire
c. yes, 7.7 cm from the 5-A wire
d. no
Answer:
c. yes, 7.7 cm from the 5-A wire
Explanation:
Given;
distance between the two wires, r = 20 cm = 0.2 m
first current, I₁ = 5.0 A
second current, I₂ = 8.0 A
The magnetic field due to the two wires occurs in different directions and it can be zero at this region.
Let x be the distance from 5 A wire where the magnetic field is zero.
[tex]B = \frac{\mu_o}{2\pi} [\frac{I_1}{x} -\frac{I_2}{r-x} ] = 0\\\\ \frac{\mu_o}{2\pi} [\frac{I_1}{x} -\frac{I_2}{r-x} ] = 0\\\\ \frac{\mu_o}{2\pi} [\frac{5}{x} -\frac{8}{0.2-x} ] = 0\\\\\frac{5}{x} -\frac{8}{0.2-x} = 0\\\\\frac{5}{x} = \frac{8}{0.2-x}\\\\5(0.2-x) = 8x\\\\1 -5x = 8x\\\\1 = 5x \ + \ 8x\\\\1 = 13x\\\\x = \frac{1}{13} \\\\x = 0.077 \ m\\\\x = 7.7 \ cm[/tex]
Therefore, the correct option is c. yes, 7.7 cm from the 5-A wire
a. If we increase the wind velocity, the maximum vertical dispersal height and rate of diffusion will decrease____.
b. If we increase the humidity, the maximum vertical dispersal height will ___________increase____ after 24 hours.
c. If we increase the lapse rate, the maximum vertical dispersal height of the pollutants will ____________________.
Answer:
a.If we increase the wind velocity, the maximum vertical dispersal height will decrease, while the rate of diffusion will increase
b.If we increase the humidity, the maximum vertical dispersal height will increase after 24 hours.
c.If we increase the lapse rate, the maximum vertical dispersal height of the pollutants will increase
Explanation:
a.If we increase the wind velocity, the maximum vertical dispersal height will decrease, while the rate of diffusion will increase
b.If we increase the humidity, the maximum vertical dispersal height will increase after 24 hours.
c.If we increase the lapse rate, the maximum vertical dispersal height of the pollutants will increase
Answer:
a decrease
b increase
c increase
what is the distance of truck and travel if it moves 7MS for 20 seconds
8+10÷5(5×4+2)=?
it ıs said that this question was very diffıcult
can you slove?
Answer:
220 bastanyan sagot ko yawa
Consider a uniformly charged sphere of total charge Q and radius R centered at the origin. We want to find the electric field inside the sphere (r
Answer:
Hello your question is incomplete attached below is the complete question
answer :
Total charge enclosed within the sphere : [tex]\frac{q_{r1} }{4\pi e_{0}R^3 } . r[/tex]
Total charge enclosed outside the sphere : [tex]\frac{q}{4\pi e_{0}r^2 } .r[/tex]
Explanation:
Given data:
Total charge of a uniformly charged sphere = Q
radius = R
first step : find the electric field inside and outside the uniformly charged sphere
2nd step : determine the total charge enclosed within and outside the sphere
make a sketch of the uniformly charged sphere
Attached below is a detailed solution
FIND THE DISTANCE BETWEEN TWO GIVEN POINTS.
1. S (5, -1) and T (5, 7)
Answer:
8 units
Explanation:
A beam of light, incident on a flat water surface, reflects from the mirror-like surface so that the angle of incidence equals the angle of reflection. The water has waves. Would individual light beams obey the law of reflection in this case?
Answer:
a protractor
Explanation:
because protractors measure angles
A factory emits pollutants at a rate of 25 g/s. The factory is located between two mountain ranges resulting in an effective valley width of 5000 m. The height of the ceiling due to atmospheric conditions is 1000 m. During the fall and spring, a breeze that travels at a velocity of 4 m/s flows through the valley. Fortunately, the breeze coming in contains no pollutants. Based on the information given, the steady state concentration of pollutants in the valley, in micrograms per cubic meter is.
Answer:
[tex]1.25\ \mu\text{g/m}^3[/tex]
Explanation:
v = Velocity of the breeze = 4 m/s
w = Width of the valley = 5000 m
h = Height of the valley = 1000 m
Volumetric flow rate is given by
[tex]\dot{V}=vwh\\\Rightarrow \dot{V}=4\times 5000\times 1000\\\Rightarrow \dot{V}=2\times10^{7}\ \text{m}^3/\text{s}[/tex]
[tex]\dot{m}[/tex] = Mass flow rate of pollutant = 25 g/s = [tex]25\times 10^6\ \mu\text{g/s}[/tex]
Concentration is given by
[tex]C=\dfrac{\dot{m}}{\dot{V}}\\\Rightarrow C=\dfrac{25\times 10^6}{2\times 10^7}\\\Rightarrow C=1.25\ \mu\text{g/m}^3[/tex]
The steady state concentration of pollutants in the valley, is [tex]1.25\ \mu\text{g/m}^3[/tex].
PLEASE ANSWER. I WILL MAKE YOU THE BEST ANSWER BRAINLIEST. I PROMISE.
Anna weighs 132 lb. Determine her mass in kilograms using the conversion 1 kg equal 2.2 lb. Use this mass to answer this question.
calculate Anna's weight on the Moon. (G = 1.6 m / S2) must include a unit with your answer
1). If 2.2 lb actually = 1 kg, then
(132lb) x (1 kg/2.2lb) = 60 kg.
(Sadly, 2.2 lb doesn't " = " 1 kg. The explanation, unfortunately, is beyond the scope of this discussion.)
2). Weight = (mass) x (gravity)
Moon weight = (60 kg)x(1.6 m/s^2)
Moon weight = 96 Newtons
During sexual reproduction, each parent contributes
Answer:
each parents contributes the dad gives the seed and the mom gives the egg
Explanation:
and then you are born
What are two benefits of scientists using a diagram to model the water cycle?
A. It can be used to show how the parts of the cycle relate to one
another.
B. It can be used to show as much detail ahis present in the actual
water cycle.
c. Only a few factors in the water cycle can be shown on the
diagram
D. It can show changes that occur in many different parts of Earth at
the same time.
Answer:
Options A. and D. are correct.
Explanation:
The water cycle shows the continuous movement of water within the Earth and atmosphere.
The two benefits of scientists using a diagram to model the water cycle are as follows:
It can be used to show how the parts of the cycle relate to one another.
It can show changes that occur in many different parts of Earth at the same time.
Options A. and D. are correct.
The loaded car of a roller coaster has mass M = 320 kg. It goes over the highest hill with a speed v of 21.4 m/s. The radius of curvature R of the hill is [01] m. (a) What is the force (N) that the track must exert on the car? (positive is up) (b) What must be the force (N) that the car exerts on a 61 kg passenger?
This question is incomplete, the complete question is;
The loaded car of a roller coaster has mass M = 320 kg. It goes over the highest hill with a speed v of 21.4 m/s. The radius of curvature R of the hill is 15.8 m.
(a) What is the force (N) that the track must exert on the car? (positive is up)
(b) What must be the force (N) that the car exerts on a 61 kg passenger?
Answer:
a) the force (N) that the track must exert on the car is -6139.14 N
b) the force (N) that the car exerts on a 61 kg passenger is -1170.27 N
Explanation:
Given the data in the question;
Let N represent the force that the track must exerted on the car
Net force on the car Fnet = Mg + N
so
M × a = Mg + N
N = Ma - Mg
N = Ma - M(v²/R)
we substitute
N = (320kg × 9.8m/s²) - ( 320 × ((21.4m/s)² / 15.8 m) )
N = 3136 - ( 320 × 28.9848 )
N = 3136 - 9275.136
N = -6139.14 N
Therefore, the force (N) that the track must exert on the car is -6139.14 N
b) What must be the force (N) that the car exerts on a 61 kg passenger?
Let N represent the force that the car exerts on 61kg passengers
so
Net force of passengers Fnet = mg + N
Ma = Mg + N
N = Ma - Mg
N = Ma - M(v²/R)
N = (61kg × 9.8m/s²) - ( 61 × ((21.4m/s)² / 15.8 m) )
N = 597.8 - ( 61 × 28.9848)
N = 597.8 - 1768.0728
N = -1170.27 N
Therefore, the force (N) that the car exerts on a 61 kg passenger is -1170.27 N
The centripetal force of the track on the car moving in the circular path is [tex]1.465 \times 10^6 \ N[/tex].
The force (N) that the car exerts on a 61 kg passenger is 597.8 N.
Centripetal force of the track
The centripetal force of the track on the car moving in the circular path is calculated as follows;
[tex]F_c = \frac{mv^2}{r}\\\\ F_c = \frac{320 \times 21.4^2}{0.1} \\\\F_c = 1.465 \times 10^6 \ N[/tex]
Normal force of the passengerThe force (N) that the car exerts on a 61 kg passenger is equal to the force the passenger exerts on the car based on Newton's third law of motion.
F = mg
F = 61 x 9.8
F = 597.8 N
Learn more about centripetal force here: https://brainly.com/question/20905151
explain the advantage of polarized sunglasses over normal tinted sunglass
Answer:
Explanation:
Polarized lenses improve vision by making colors appear deeper and bolder and eliminating uncomfortable and often dangerous glare, as well as filtering harmful ultraviolet light
State four factors affecting thermal conductivity
Answer:
∙ Temperature
∙ Concentration of electrolyte
∙ Nature of the electrolyte added
∙ Nature of solvent and its viscosity
Explanation:
Stored energy due to vertical position is known as
Elastic Potential energy
Vibrational energy
Kinetic energy
O Gravitational Potential energy
1
2
3
4
5
Answer: gravitational potential energy
Explanation:
If you have a 0.125 kg lead piece at
20.0°C, how much heat must you
add to melt it? (Remember, you
must warm it to its melting point
first.)
Material
Lead
Melt Pt (°C)
327
L (1/kg)
2.32.104
Boil Pt (°C) Lv (1/kg)
1750 8.59.105
c (1/(kg*c)
128
(Unit = J)
Answer:
7,812 J
Explanation:
Using the relation:
Q = mcΔθ
Q = quantity of heat
C = specific heat capacity of lead
Δθ = temperature change (T2 - T1)
M = mass of substance
Q = mass * specific heat * Δθ
Q = 0.125kg * 128 * (327 – 20)
Q = 0.125 * 128 * 307
Q = 4912 J
For melting:
Q = mass * Hf
0.125 * (2.32 * 10^4)
= 2,900 J
Total = 4,912 J + 2,900 J = 7,812 J
Which pair of labels is correct? A: Maximum kinetic energy C: Maximum gravitational potential energy B: Maximum kinetic energy D: Maximum gravitational potential energy A: Maximum gravitational potential energy C: Maximum kinetic energy B: Maximum gravitational potential energy D: Maximum kinetic energy
Answer: C. A:Maximum gravitational potential energy C: Maximum kinetic energy
Explanation:
Need help only in part C!
An electric space heater draws 15.0 A from a 120-V source. It is operated, on the average, for 5.0 h each day. a. How much power does the heater use ? b. How much energy in kWh does it consume in 30 days? C. AED 0.30 per kWh , how much does it cost to operate the heater for 30 days ?
Answer:
A. 1800 Watt
B. 10.8 KW/h
C. AED 3.24
Explanation:
A. Determination of the power.
Voltage (V) = 120 V
Current (I) = 15 A
Power (P) =?
P = IV
P = 15 × 120
P = 1800 Watt
B. Determination of the energy consumption in KW/h for 30 days
We'll begin by converting 1800 Watt to kilowatt. This can be obtained as follow:
1000 W = 1 KW
Therefore,
1800 W = 1800 W × 1 KW / 1000 W
1800 W = 1.8 KW
Next, we shall determine the energy consumption per day. This can be obtained as follow:
Power (P) = 1.8 KW
Time (t) = 5 hour per day
Energy (E) =?
E = P /t
E = 1.8 / 5
E = 0.36 KW/h per day.
Finally, we shall determine the energy consumption in 30 days. This can be obtained as follow:
1 day = 0.36 KW/h
Therefore,
30 days = 30 × 0.36 KW/h
30 days = 10.8 KW/h
Thus, the energy consumption in 30 days is 10.8 KW/h
C. Determination of the cost of operation in 30 days.
1 KW/h = AED 0.30
Therefore,
10.8 KW/h = 10.8 KW/h × AED 0.3 / 1 KW/h
10.8 KW/h = AED 3.24
Thus, the cost of operation in 30 days is AED 3.24
Answer:
1800 W
Explanation:
