Answer: A chemical formula is a way of showing and representing information about a chemical proportion of atoms that constitute a particular chemical compound or molecule
List out Units For: Acceleration
Unit for Acceleration is m/s² or ms raised to -2
A freshly prepared sample of radioactive isotope has an activity of 10 mCi. After 4 hours, its activity is 8 mCi. Find: (a) the decay constant and half-life T1/2; (b) How many atoms of the isotope were contained in the freshly prepared sample? (c) What is the sample's activity 30 hours after it is prepared?
Answer:
(a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]
The half life is 11.3 hr.
(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]
(c). The sample's activity is 1.87 mCi.
Explanation:
Given that,
Activity [tex]R_{0}=10\ mCi[/tex]
Time [tex]t_{1}=4\ hours[/tex]
Activity R= 8 mCi
(a). We need to calculate the decay constant
Using formula of activity
[tex]R=R_{0}e^{-\lambda t}[/tex]
[tex]\lambda=\dfrac{1}{t}ln(\dfrac{R_{0}}{R})[/tex]
Put the value into the formula
[tex]\lambda=\dfrac{1}{4\times3600}ln(\dfrac{10}{8})[/tex]
[tex]\lambda=0.0000154\ s^{-1}[/tex]
[tex]\lambda=1.55\times10^{-5}\ s^{-1}[/tex]
We need to calculate the half life
Using formula of half life
[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{\lambda}[/tex]
Put the value into the formula
[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{1.55\times10^{-5}}[/tex]
[tex]T_{\dfrac{1}{2}}=44.719\times10^{3}\ s[/tex]
[tex]T_{\dfrac{1}{2}}=11.3\ hr[/tex]
(b). We need to calculate the value of N₀
Using formula of [tex]N_{0}[/tex]
[tex]N_{0}=\dfrac{3.70\times10^{6}}{\lambda}[/tex]
Put the value into the formula
[tex]N_{0}=\dfrac{3.70\times10^{6}}{1.55\times10^{-5}}[/tex]
[tex]N_{0}=2.38\times10^{11}\ nuclei[/tex]
(c). We need to calculate the sample's activity
Using formula of activity
[tex]R=R_{0}e^{-\lambda\times t}[/tex]
Put the value intyo the formula
[tex]R=10e^{-(1.55\times10^{-5}\times30\times3600)}[/tex]
[tex]R=1.87\ mCi[/tex]
Hence, (a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]
The half life is 11.3 hr.
(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]
(c). The sample's activity is 1.87 mCi.
can we add 2 atoms together? 3? How do particles combine to form the variety of matter one observes?
In economics, _________ is the amount of a resource that firms and producers are willing and able to provide to the marketplace
sectors are the amount of resources
A student is on a skateboard facing a wall. The student and skateboard have a mass of 75 kilograms. The student pushes off of the wall with a force of 100 Newtons. What is the force of the wall pushing back on the student? What is the acceleration of the student as she moves away from the wall?
Answer:
F=-100N; a=1.3m/s^2
Explanation:
Force is being made by student, so wall counteracts that force by not moving so it is equally opposite.
The force of the wall pushing back on the student would be 100 Newtons, and the acceleration of the student as she moves away from the wall would be 1.33 m/s²
What is Newton's third law of motion?Newton's third law of motion state that for every action force there exists a complementary reaction force that balances it.
As given in the problem a student is on a skateboard facing a wall. The student and skateboard have a mass of 75 kilograms. The student pushes off of the wall with a force of 100 Newtons,
The force of the wall pushing back the student = 100 Newtons
The acceleration of the student = 100/75
=1.33 m/s²
Thus, The student would be pushed back against the wall by a force of 100 Newtons, and she would accelerate away from the wall at a rate of 1.33 m/s².
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Will was riding his bike when a dog ran out in front of him. He slammed on his brakes. During this quick stop, some of the mechanical energy (his motion) was changed into
A) heat energy.
B) light energy.
C) kinetic energy.
D) gravitational energy.
Answer:
A
Explanation:
big brain
During this quick stop, some of the mechanical energy (his motion) was changed into heat energy.
What is energy?Energy is the ability to do work. There are different types of energy such as Heat energy, light energy, kinetic energy, and gravitational energy.
Heat is the energy that moves from one body to another when temperatures are different. Heat passes from the hotter to the colder body when two bodies with differing temperatures are brought together.
The joule is a unit of energy that serves as the SI unit for heat (J). The calorie (cal), which is defined as "the amount of heat necessary to raise the temperature of one gram of water from 14.5 degrees Celsius to 15.5 degrees Celsius," is another common unit of heat measurement.
Therefore, During this quick stop, some of the mechanical energy (his motion) was changed into heat energy.
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Why does sonar use ultrasound rather than sound?
Answer; Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances.
Answer:
Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances
Explanation:
1. According to Newton's third law of motion, how are action
and reaction forces related?
2. How is momentum conserved?
3. Suppose you and a friend, who has exactly twice your mass,
are on skates. You push away from your friend. How does the
force with which you push your friend compare to the force
with which your friend
pushes you? How do your
accelerations compare?
4. Thinking Critical be ly comparing and Contrasting
Which has more momentum, a 250-kg dolphin swimming
at 6 m/s, or a 450-kg manatee swimming at 2 m/s?
(need 1-4 answered ASAP)
Answer:
you couldn't do this on your own or search it up on google
how much force is needed to accelerate 300 kg at a rate of 4 m/s/s
Answer:
1200
Explanation:
Force = Mass x Acceleration
Answer:
[tex]\boxed {\tt 1,200 \ Newtons }[/tex]
Explanation:
Force can be found by multiplying the mass by the acceleration.
[tex]F=m*a[/tex]
The mass is 300 kilograms.
The acceleration is 4 meters per second squared.
[tex]m= 300 \ kg\\a= 4 \ m/s^2[/tex]
Substitute the values into the formula.
[tex]F= 300 \ kg * 4 \ m/s^2[/tex]
Multiply.
[tex]F= 1200 \ kg * m/s^2[/tex]
1 Newton is equal to 1 kilograms meters per second squared, so our current answer of 1200 kg m/s² is equal to 1200 Newtons.
[tex]F= 1200 \ N[/tex]
The force needed is 1,200 Newtons.
Which event is an example of condensation?
A. Wet clothes are drying on a clothesline.
B. A mirror fogs up when someone takes a hot shower.
C. Water drips from an icicle on the edge of a roof.
O D. Rain turns to sleet as it nears the ground.
Answer:
the answer to your question is b a mirror fogs up when someone takes a hot shower.
The process of conversion of gaseous water to its liquid form is called condensation. The fogs formed on the mirror from the hot shower is an example of condensation.
What is condensation?Condensation is the process of cooling up of water vapor to liquid water. Water vapor condenses when it cools. Condensation can be best understood from the reason behind raining.
When water vaporizers from resources and cools from the sky, and the vapor condenses to form liquid droplets. Similarly we can observe water droplets in the window pane due to the similar effect.
The water vapor arises from the hot shower condenses in the atmosphere and forms the drops on the mirror. Therefore, the mirror fogs up by the hot shower is an example of condensation.
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please help im dying
Dos pilotos suicidas, que están inicialmente a una distancia de 500 m entre sí, deciden chocar directamente de frente arrancando ambos desde el reposo. Ambos autos pueden desarrollar una aceleración máxima constante de 15 m/s2 . Si el piloto A arranca un segundo antes que el piloto B, encuentra: a) la posición donde los autos chocan, medida a partir de la posición donde arranca el piloto A, y b) la rapidez relativa de la colisión (la rapidez de B con respecto a A justo antes de la colisión, ó viceversa).
Answer:
a) El punto de colisión de los dos automóviles desde donde parte el conductor del automóvil A es de aproximadamente 293,14 metros.
b) La velocidad del automóvil A, en relación con la velocidad del automóvil B, es de 15 m / s
Explanation:
Los parámetros del movimiento son;
La distancia entre ambos coches = 500 m
La aceleración de ambos coches = 15 m / s²
La dirección de movimiento de ambos coches = uno hacia el otro
La hora de inicio del conductor A = Un segundo antes de la hora de inicio del conductor B
Por lo tanto, de la ecuación de movimiento, tenemos;
s = u · t + 1/2 · a · t²
v² = u² + 2 · a · s
Dónde;
u = La velocidad inicial de los autos = 0 (los autos parten del reposo)
t = El tiempo de movimiento de una aceleración dada
a = La aceleración = 15 m / s²
s = La distancia recorrida en el tiempo t
Por lo tanto, para el controlador A, tenemos;
s₁ = 0 × (t + 1) + 1/2 × 15 × (t + 1) ² = 7.5 × (t + 1) ²
s₁ = 7.5 × (t + 1) ²
Para el conductor B, tenemos;
s₂ = 0 × t + 1/2 × 15 × t² = 7.5 × t²
s₂ = 7,5 × t²
Dado que ambos chocan a lo largo del camino de 500 m, tenemos;
s₁ + s₂ = 500 metros
∴ 7.5 × (t + 1) ² + 7.5 × t² = 500
∵ s₁ + s₂ = 7.5 × (t + 1) ² + 7.5 × t²
Lo que da;
15 · t² + 15 · t + 7.5 = 500
15 · t² + 15 · t - 492,5 = 0
Resolver usando la aplicación en línea da; t = -6,25181 o t = 5,25181
Dado que t es un número natural, tenemos el valor correcto para t = 5.25181 segundos
a) Por tanto, el punto de colisión de los dos coches desde donde parte el conductor del coche A es;
s₁ = 7.5 × (t + 1) ² = 7.5 × (5.25181 + 1) ² ≈ 293.14 metros
El punto de colisión de los dos automóviles desde donde parte el conductor del automóvil A ≈ 293,14 metros
b) La semilla de A en el punto de colisión se da de la siguiente manera
Velocidad, v₁ = u + a × (t + 1) = 0 + 15 × (5.25181 + 1) ≈ 93.78
v₁ ≈ 93,78 m / s
La semilla de B en el punto de colisión también se da de la siguiente manera
Velocidad, v = u + a × (t) = 0 + 15 × 5.25181 ≈ 78.78
v₁ ≈ 78,78 m / s
Por lo tanto, la velocidad del automóvil A, en relación con la velocidad del automóvil B, [tex]v_{relative}[/tex] se da como sigue;
= v₁ - v₂ = 93,78 m / s - 78,78 m / s = 15 m / s
la velocidad del automóvil A, relativa a la velocidad del automóvil B = 15 m/s.
Protons are found only in the atomic nucleus.
TRUE
FALSE
Answer:
true
Explanation:
Protons and neutrons are found in the nucleus
A toy car rolls down a hill starting from rest. After 4.2 seconds its velocity is 18 meters per second. What is the acceleration of the car ?
SOMEONE PLZ HELP :(
WILL MARK BRAILIEST
Answer: if this is the same question I think it’s 24
Explanation:
Three toy boats with the same mass were in a lake. Two boats were moving and one was stopped. Each boat got bumped by another boat, but not in the same direction. All the boats changed speed as a result of being bumped. Use the information in the diagram to answer. Which toy boat exprienced the strongest force when it was bumped ? How do you know ?
The answer is " The orange and gray toy boats experienced the strongest force because both gained the same force as they sped up the blue boat lost force so it slow down
Explanation:
Trust me I did this one for an assignment
The boat that will experience the strongest force is the boat that has the highest speed.
According to Newton's second law of motion, the force applied to an object is directly proportional to the product of mass and acceleration of the object.
F = ma
[tex]F = \frac{mv}{t}[/tex]
where;
F is the force experienced by the objectv is the velocity of the objectt is the time of motionThe force experienced by the boats is directly proportional to the velocity of their motion. Since the boats have the same mass, the force experienced by each boat will depend on the speed with which the boat moves.
Thus, the boat that will experience the strongest force is the boat that has the highest speed.
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What is the name of the kind of stretch that involves stretching as far as you can and then holding for 10-30 seconds
Question 2 options:
PNF
ballistic
dynamic
static
Answer:
Static stretching.
Explanation:
It is static stretching because it is a form of stretching which u can do actively for a period of time and you hold position for about 30 to 60 seconds which allow the muscles and connective tissues to lengthen. It is done after work out with out movement in order to loosen up muscles so as to gain flexibility.
what does the galaxy made of ?
2
How is acceleration related to force when mass is constant, according to Newton's second law of motion?
A. The acceleration is directly proportional to the net force,
OB
The acceleration is inversely proportional to the net force.
C. The acceleration is inversely proportional to the square root of the net force.
OD
The acceleration is directly proportional to the square root of the net force.
Reset
Next Question
Answer:
A
Explanation:
The acceleration of an object is directly proportional to its net force.
[tex]a = \frac{f}{m} [/tex]
Answer:
Correct choice: A. The acceleration is directly proportional to the net force
Explanation:
Newton's Second Law of Motion
According to Newton's second law of motion, the acceleration of an object is directly proportional to the net force F and inversely proportional to the object's mass m:
[tex]\displaystyle a=\frac{F}{m}[/tex]
Correct choice: A. The acceleration is directly proportional to the net force
A dog is 60 m away while moving at a constant velocity of 10 m/s towards you. How Long will it be before the dog is close enough to your face?
Answer:
6 seconds
Explanation:
The answer is 6 because if the dog is going 10 m/s it will take 6 seconds to get from 60 meters away to you.
Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs.
Which statement about work and power describes Hiro’s actions?
He did more work running than walking.
He did more work walking than running.
He had more power running than walking.
He had more power walking than running.
Answer:
C) he had more power running than walking
Explanation:
saw it on a quizlet. not 100% sure tho
Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs so He had more power running than walking.
What is power?In physics, power is the amount of energy transferred or converted per unit of time. In the International System of Units, the unit of power is the watt, equal to one joule per second. In older works, power is sometimes called activity. Power is a scalar quantity.
Power is related to other quantities; for example, the power involved in moving a ground vehicle is the product of the traction force on the wheels and the velocity of the vehicle.
The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft
Since we know that Hiro will run on stairs to minimize the time of reaching his home so if time decreases then he has to increase his power as power is the ratio of work and time.
Hence Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs so He had more power running than walking.
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A runner moves at an average speed of 3.0 m/s and covers 9.5 km. In seconds, how long does the run take?
28.5 s
29.0 s
3.16 s
3200 s
Answer:
3200 seconds
Explanation:
If he ran at 3 m/s for 28.5 seconds, he would have run 85.5 meters
29 seconds would be 87 meters run not 9.5 km
Find the resultant of an easterly force of 100 N and a southeast force of 80 N acting at 65 degrees to the 100 N force
Answer:
Resultant is 152 N at 28.5 degrees south to the 100 N force
Explanation:
Question 4 of 20
Luke wraps a magnetized steel nail with several coils of insulated wire and
then connects the loose ends of the wire to a 10 W lightbulb. Which step
could he take next to get the lightbulb to light up?
O A. Replace the magnetized nail with a nonmagnetic metal to cause
an electric current to flow in the wire.
O B. Remove the magnetized nail from the wire coil to induce a
magnetic field that will flow through the wire.
C. Move the magnetized nail back and forth within the wire coil to
induce an electric current in the wire.
D. Add several more coils of the wire around the magnetized nail to
make a stronger electric current.
SUBMIT
Answer:
C. Move the magnetized nail back and forth within the wire coil to induce an electric current in the wire.
Hope this helps.
Which model of the atom has electrons traveling in specific paths around the nucleus? Bohr's model Rutherford's model Thomson's model Dalton's model
Answer:
A, Bohr's model
Explanation:
Took the quiz, hope it's right for you.
(The other three did have something to do with it they just didn't create that specific model)
The model of the atom that has electrons traveling in specific paths around the nucleus is Rutherford's model.
Therefore, the correct answer is option B
J. J Thomson proposed that the atom is a sphere of positively charged matter in which negatively charged electron are embedded.
In Rutherford's model of atomic structure, the electrons moves in orbits by electrostatic attraction to the positively charged nucleus.
According to Dalton's atomic theory, atom were indestructible and indivisible solid particle.
Bohr's model made assumption that electron can only exist in circular orbits of definite quantum energy.
According to the question, the model of the atom that has electrons traveling in specific paths around the nucleus is Rutherford's model.
Therefore, the correct answer is option B
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How are velocity, wavelength, and frequency related
Answer:
The wave velocity and the wavelength are related to the wave's frequency and period by vw=λT or vw=fλ. The time for one complete wave cycle is the period T. The number of waves per unit time is the frequency ƒ. The wave frequency and the period are inversely related to one another.
Explanation:
protons are present in sodium atom.
a 11
b 10
C 12
d 9
11
Explanation:
There are 11 protons in a sodium atom
A force of 75 N at an angle of 15° to the direction of motion moves a chair 3 m. Which change would result in more work being done on the chair?
Answer:
Decreasing the angle to 10
Explanation:
Edge 2020
At a race car driving event, a staff member notices that the skid marks left by the race car are 9.06 m long. The very experienced staff member knows that the deceleration of a car when skidding is -40.52 m/s2. What can the staff member estimate for the original speed of the race car if it came to a stop during the skid?
Answer:
27.1 m/s
Explanation:
Given that at a race car driving event, a staff member notices that the skid marks left by the race car are 9.06 m long. The very experienced staff member knows that the deceleration of a car when skidding is -40.52 m/s2.
Using third equation of motion,
V^2 = U^2 + 2aS
Since the car is decelerating, the final velocity V = 0
Substitute all the parameter into the equation above,
0 = U^2 - 2 * 40.52 * 9.06
U^2 = 734.22
U = [tex]\sqrt{734.22}[/tex]
U = 27.096
U = 27.1 m/s approximately
Therefore, the staff member can estimate for the original speed of the race car to be 27.1 m/s if it came to a stop during the skid
#7 If the Moon’s mass was suddenly tripled, what would occur to the gravitational force between the Earth and the Moon?
(A) Gravitational force would increase by a factor of 3.
(B) Gravitational force would decrease by a factor of 3.
(C) Gravitational force would increase by a factor of 9.
(D) Gravitational force would decrease by a factor of 9.
Answer:
well it would be (A) Gravitational force would increase by a factor of 3.
Explanation:
because the moon is the only thing that gained mass not the Earth
An ant is crawling along a yardstick that is pointed with the 0-inch mark to the east and the 36-inch mark to the west. It starts at the 14-inch mark, crawls to the 20-inch mark, then moves to the 16-inch mark. What was the total distance the ant traveled?
Given :
An ant is crawling along a yardstick that is pointed with the 0-inch mark to the east and the 36-inch mark to the west.
It starts at the 14-inch mark, crawls to the 20-inch mark, then moves to the 16-inch mark.
To Find :
The total distance the ant traveled.
Solution :
Total distance travelled by ant = (distance between 14 and 20 inch mark) +
(distance between 20 and 16 inch mark)
Total distance = (20-14 ) + ( 20-16) = 6 + 4 = 10 inch.
Therefore, total distance the ant traveled is 10 inch.
Hence, this is the required solution.