The correct statement about the very first stars in the universe is that they were made only from hydrogen and helium.
What is universe?
The universe is the totality of existence, encompassing all matter, energy, space, and time, and the physical laws and constants that govern them. It is the sum total of all that exists, was, and will be, including all galaxies, planets, stars, and phenomena such as light, gravity, and electromagnetic radiation. The universe is believed to have originated with a massive explosion known as the Big Bang, estimated to have occurred around 13.8 billion years ago. Since then, the universe has been expanding outward, ever increasing in size, complexity, and energy density. Scientists believe that the universe is composed of a vast array of components, including dark matter, dark energy, and dark radiation.
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When a car has a dead battery, it can often be started by connecting the battery from another car across its terminals. The positive terminals are connected together as are the negative terminals. The connection is illustrated in Fig. P1.15. Assume the current i in Fig. P1.15 is measured and found to be 30A. a) Which car has the dead battery? b) If this connection is maintained for 1 min, how much energy is transferred to the dead battery?
Explanation:
convert 1= 30 amp
which Car has the dead
battery ?
CarA
Car B
Ams => The Current i flows into the of the Battery of Qax A.
Posithe terminal
So. By using Passinge sign Convention.
Power P₁ = Vi = 12X 30
PA = 360 Watt (the)
=>Power is Positive So Car Ahabsorbing So now we can say car A has dead battery.
Power,
Connection is maintained for t = 1 min. Energy toonsffered to the dead battery
=> we know w(t) = Work = Emergy t S. Pdt fo W (1 = imin) = 360 dt
t = 60 sec = 1 min.
36. (t), 60
360 X60
|w[t=1mm) = 21.60 *Jure.
What area of glass is needed to support a mass of 1000 kg if the glass can withstand a maximum pressure of
20kPa?
Answer:
since, Pressure=Force/Area
then,Area=Force/Pressure
or,Area=20000/1000
:.Area=20 m²
PLEASE ANSWER 100 POINTS!!
Juan drives his car around a curve at a speed of 17.0 m/s. Assume the curve can be approximated by an arc of a circle of radius 122.0 m. If a force of 7380 N is required to maintain the car’s circular motion, what is the car’s mass?
In ∑ F = m v^2r , both m and r are unknown but remain constant
What is the centripetal force that allows a car to move around a sharp curve in a roadway?
Any force, or set of forces, can accelerate an object radially or centripetally. A few examples include the tension in a tether ball's rope, the gravitational pull of the Earth on the Moon, the friction between roller skates and a rink's floor, the force of a banked road on a car, and the forces on a centrifuge's tube.
A centripetal force is any net force that produces uniform circular motion. The centripetal force and centripetal acceleration both point in the direction of the centre of curvature. Newton's second equation of motion states that net force equals mass times acceleration, or net F = m a.
The centripetal acceleration—a = a c—determines the rate of acceleration for uniform circular motion.
Consequently, the size of
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Please help! 50 points.
A student conducts an experiment to test how the temperature affects the amount of salt that can dissolve in water. In the experiment, she uses 150 milliliters of water in each trial and stirs for five minutes each time.
What is the dependent variable in this experiment?
the temperature of the water
the amount of water
the amount of salt
the time stirred
Answer:
i think its time stirred, double check. i hope it helped ;)
Explanation:
If 10.0 g of water is initially heated from 20°C to 100°C, and then it is continually heated through its phase change (it is vaporised), what is the total amount of energy necessary to carry out this process?
Answer:
The total amount of energy necessary to carry out this process is 22600 joules (J).
Explanation:
This is because the heat of vaporization (the energy required to change the state of water from liquid to gas) of water is 2260 J/g. Since 10.0 g of water is being heated, the total amount of energy needed is 10.0 g * 2260 J/g = 22600 J.
1
Glucose provides energy for cells. Different cells have different mechanisms for glucose intake. Intestinal cells contain proteins that transport glucose against its concentration gradient. These proteins couple the movement of glucose to the movement of sodium down its concentration gradient. Red blood cells have transporter proteins embedded in their membranes. When bound by a glucose molecule, these proteins change shape and allow glucose to move down its concentration gradient into the cell.
Based on this information, what type of transport is used for glucose in blood and intestinal cells?
A.
Both blood and intestinal cells take in glucose by passive transport.
B.
Blood cells take in glucose by passive transport and intestinal cells take in glucose by active transport.
C.
Both blood and intestinal cells take in glucose by active transport.
D.
Blood cells take in glucose by active transport and intestinal cells take in glucose by passive transport.
Answer:
C. In the passage, it seems that both of the cells have the same job, so I would go with C.
How much would you have to pay SP Services if you
used two 40 W lamps and a 120 W television for 5 hour a
day for the month of April? (Assume the cost of 1 kWh
of energy to be 16 cents).
Answer:
$4.80
Explanation:
Total energy used is found with this formula:
[tex]E = Pt[/tex]
where:
[tex]E[/tex] is energy (in kilowatt-hours)
[tex]P\\[/tex] is power ( in Kilowatts)
[tex]t[/tex] is time ( in Hours)
We can find the total power consumption by adding all the appliances, then dividing by 1000 to convert it from Watts to Kilowatts:
[tex]\frac{(40*2)+120}{1000} =0.2kW[/tex]
And then find [tex]E[/tex] with 5 hours a day for 30 days:
[tex]E= 0.2*(5*30)=30kWh[/tex]
Thus, cost needed would be:
$0.16 × 30 = $4.80
What is a pivot arm lever?
The forearm serves as the lever arm, while the elbow serves as the pivot. In spite of the forearm's weight and whatever additional weight the hand may be bearing, the biceps muscle exerts the force and bends the forearm. Compared to the effort, the weight is further from the pivot.
A moving bar that pivots on a fulcrum fastened to a fixed point is the lever. The lever works by exerting forces at various angles in relation to the pivot or fulcrum. Ones farther from this pivot move more quickly than points closer to it when the lever revolves around the fulcrum.
A moving bar that pivots on a fulcrum fastened to a fixed point is the lever. The lever works by exerting forces at various angles in relation to the pivot or fulcrum. Ones farther from this pivot move more quickly than points closer to it when the lever revolves around the fulcrum.
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a log with a mass of 14 kg is suspended by two ropes, one at either end. What is the tension force in each rope
According to the given statement The tension force in each rope is T = 14g/2Sin N, according to the information provided.
What is tension force ?Tension is the force that is transmitted through a cable, rope, or wires when it is stretched by loads exerted from opposing sides. The bodies are put through an identical degree of strain at each end of the wire by the tension force, which is exerted all along entire of the wire's length.
Let the tension in each rope be T₁ & T₂
Also, T₁ = T₂ = T
T₁ Sinθ + T₂ Sinθ = mg
2T Sinθ = mg
2T Sinθ = 14g
T = 14g/2Sinθ
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Energy due to motion and energy due to position (such as height) are both categorized as kinds of _______.
Answer:
Mechanical energy.
Explanation:
Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy or potential energy.
What is the acceleration when t 0?
The acceleration of the particle at t=0 is zero because the particle is in rest position and did not moving at any of the instance or travelling at an uniform speed through out the whole journey or yet did not start from the source point.
Acceleration is the rate of change of velocity. At any point on a trajectory, the magnitude of the acceleration is given by the rate of change of velocity in both magnitude and direction. Acceleration of the body that we can consider is the increasing value of the velocity of any object at a constant rate and that of wee can calculate. Hence by the primary information that we have we can formerly consider that the acceleration which is acting on the particle at t=0 is zero because the particle is in rest position and did not moving at any of the instance or travelling at an uniform speed through out the whole journey or yet did not start from the source point.
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A hand pump suitable for inflating a football has a cylinder which is 0.24m in length and an internal cross-sectional area of 5.0 x 10 -4 m 2 . To inflate the football the pump handle is pushed in and air is pumped through a one-way valve. The valve opens to let air in to the ball when the air pressure in the pump has reached 150 000 pa. (Assume the air temperature remains constant}
a) If the pressure in the pump is initially 100 000 pa, calculate how far the piston must be pushed inwards before the one way valves opens.
(b) When the one-way valve opens the total pressure in the cylinder will be 150 000 pa. What force will be exerted on the piston by the air in the cylinder?
The distance the piston needs to travel for the valve to open is equal to the applied force divided by the area, which is equal to 0.1 m.
What is applied force?
Applied force is a type of force that is applied to an object or system in order to cause it to move, accelerate, or change its shape. This type of force is often generated by machines and other devices, and can also be exerted by humans.
Applied force can also be used to counter other forces, such as gravity, friction, and inertia. Applied force is measured in newtons (N).
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A mosquito runs head-on into a truck. Splat! Which is true during the collision? A. The mosquito exerts more force on the truck than the truck exerts on the mosquito. B. The truck exerts more force on the mosquito than the mosquito exerts on the truck. C. The mosquito exerts the same force on the truck as the truck exerts on the mosquito. D. The truck exerts a force on the mosquito but the mosquito does not exert a force on the truck. E. The mosquito exerts a force on the truck but the truck does not exert a force on the mosquito.
The truck exerts more force on the mosquito than the mosquito exerts on the truck is true during the collision.
What is the exerts?
Exerts is a term used to describe a passage or an extract taken from a larger piece of writing. Exerts are often used to showcase a specific part of a work and can be used to highlight the most important or influential passages. Exerts can be used to support or illustrate an argument, and can be used to provide evidence for a point that is being made. Exerts are often found in essays, scholarly articles, and other forms of writing, and are a useful tool for authors to draw attention to certain points or ideas.
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replace the force system acting on the post by a resultant force and couple moment at point o
By replacing the force system acting on the post with a resultant force and a couple of moments at point o we get total momentum of 1478.85 ft-lb.
As per the figure we have 3 forces: At the top 300lb left side 150lnb and at the middle 200lb.
first, we have to break down the forces into x and y components.
Now calculating each force separately:
∑Fₓ=300lb+cos 30°-150×4/3+200
=259.81-120+200
∑Fₓ=339.81lb.
Now, calculate the sum of y components.
∑Fy=300 sin 30°+150×3/5
∑Fy=300 sin 30°+90
∑Fy=240lb
Now we have to x and y components by these values we can find the actual force.
|F|=√Fx²+Fy²
|F|=√(339.81)²+(240)² α=tan⁻¹(∑Fₓ/∑Fy)
|F|=√115470.83+57600 α=tan⁻¹(339.81/240)
|F|=√173070 α=35.23°
|F|=416.02 and 35.23°
the sum of moments at O
∑Mo=-Fx₃×2+Fx₂×4-Fx₁×6
∑Mo=-200(2)+4/5 150*4-3000cos30°(6)
∑Mo=-400+480-277.65
=1478.85ftlb
∑Mo=1478.85ftlb
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The current in a ________
Answer here
circuit is the same at every point?
Answer:
Series.
Explanation:
Current is the same in each device since there is only a single pathway for the charge to flow.
Two friends A and B started at different times and covered 30km as shown in the graph.
Identify the correct statement from the following.
option 1 - A and B move with the same speed
option 2 - B moves with non-uniform speed
option 3 - A completes his journey early
option 4 - B overtakes A at 11:10 a.m.
Answer:
Explanation:
option 1 - A and B move with the same speed INCORRECT because the lines have different slopes
option 2 - B moves with non-uniform speed INCORRECT because the line for B is straight
option 3 - A completes his journey early INCORRECT because A ends his journey at about 11:45 after going about 42 km. B finishes his journey at about 11:35.
option 4 - B overtakes A at 11:10 a.m. CORRECT. They meet at the 30 km mark at 11:10, which is where the lines intersect.
Based on the age of the light- and dark-colored regions of the Moon and the number of craters observed in these regions, we know that impacts in the inner Solar System:
Based on the age of the light- and dark-colored regions of the Moon and the number of craters observed in these regions, we know that impacts in the inner Solar System rapidly decreased approximately 3 billion years ago.
The light-colored areas of the Moon's surface are roughly 1 billion years older than the dark-colored regions.
The dark patches are basalt-based juvenile plains known as maria. The basalt poured in and inundated the region left by a massive asteroid or comet collision. The bright regions are the highlands, which are raised mountains caused by impacts.
The light-colored material is found in portions of the Moon known as the highlands, which represent the Moon's oldest crust.
The lunar highlands are the earliest lunar features. This is mostly determined by the amount of impact craters found in various locations of the moon.
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Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass is doubled, what happens to the cart's acceleration
According to the given statement If suddenly a load is dumped into the cart so that the cart's mass is doubled The acceleration slows.
Give an explanation of acceleration.which speaks of the rate of change in time of the speed and direction of motion. Something is said to be accelerating when it starts to move faster or slower. Even if the speed slows down, motion on a circle accelerates because the direction is constantly changing.
Does accelerating mean going faster?Any process in which the velocity changes is referred to as acceleration. There are only two ways to speed up because velocity consists of both a speed and a direction.
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A worker is testing a multiple pulley system to estimate the heaviest object that he could lift. The largest downward force he can exert is equal to his weight, 875 N. When the worker moves the rope 1. 5 m, the object moves 0. 25 m. What is the heaviest object that he could lift?
Force is positive if the mass accelerates downward. Use the formula T = M x A to determine the tension in the rope.
How is the force in a pulley system calculated?That direction is the pull that is referred to as tension. As a result, the tension will point toward the string or rope and away from the mass.
A mass suspended by a string is pulled upward by the string, exerting an upper force that shifts the tension to the upper side.
For instance, you should know that T = 9g x 2m/s2 = 18gm/s2 or 18N when trying to calculate T in a straightforward pulley system with a linked mass of 9g and an upward acceleration of 2m/s2 (newtons). The direction in which a string expands changes when it passes over an ideal massless pulley, but the string's tension is unaffected.
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in order to catch a ball, a baseball player moves his or her hand backward in the direction of the balls motion. doing this reduces the force of impact on the players hand principally because....
a.) the time of impact is decreased
b.) the time of impact is increased
c.)the velocity of the hand is reduced
d.) the momentum of impact is reduced
e.) none of the above
The right response is B: To catch a ball, a baseball player moves his or her hand backward in the direction of the ball's motion because the time of impact is increased.
By doing this, the force of impact on the player's hand is mostly reduced. The force needed to stop the ball will decrease as the amount of time it takes to reach zero motion increases. Consider a ball approaching you with 100 units of momentum. To stop the ball, a 100-unit impulse would be necessary. No matter how the impulse is generated, there must be 100 units of it. A force is an effect that can alter an object's motion in physics.
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A 40 kg boy dives horizontally off a 600 kg raft. If the boy's speed at the moment he is leaving the raft is 4.0 m/s, what is the raft's speed
A boy weighing 40 kg jumps off a 600 kg raft horizontally. If the youngster is leaving the raft at a velocity of 4.0 m/s, the raft will be moving at a speed of 0.26 m/s.
The conservation of linear momentum is a general law of physics that states that no single item, or system of objects, experiences a change in the quantity called momentum that describes motion. Momentum is the force needed to stop an item moving at a certain speed in a given amount of time. It is calculated by multiplying an object's mass by its velocity.
Given,
mass of the boy (m₁) = 40 kg
mass of the raft (m₂) = 600 kg
speed of the boy (u₁) = 4 m/s
We have to find out the speed of the raft (u₂)
By conservation of linear momentum, We get
m₁u₁ = m₂u₂
⇒ u₂ = (m₁ ₓ u₁)/m₂
⇒ u₂ = (40*4)/600
⇒ u₂ = 0.26 m/s
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Why does temperature have no effect on mass?
The amount of matter present is simply referred to as mass. As a result, temperature change has no direct effect on mass since the amount of matter present remains constant regardless of temperature. The mass of a material in a given volume is defined as its density.
Temperature is a physical measure that quantifies our feelings of hotness and coolness. A thermometer is used to measure temperature.
Thermometers are calibrated in a variety of temperature scales that have traditionally been defined by various reference points and thermometric substances.
The most prevalent scales are the Celsius scale (previously known as centigrade), the Fahrenheit scale (°F), and the Kelvin scale (K), with the latter being used mostly for scientific reasons. The kelvin is one of the International System of Units' seven basic units (SI).
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A spring with a cart at its end vibrates at frequency 5.0Hz\;Hz .
A. Determine the period of vibration.
B. Determine the frequency if the cart's mass is doubled while the spring constant remains unchanged.
C. Determine the frequency if the spring constant doubles while the cart's mass remains the same.
A. The period of vibration is the time it takes for one complete oscillation to occur. It is the reciprocal of the frequency. The period of vibration can be calculated using the formula:
Period = 1/Frequency
Given that the frequency of vibration is 5.0Hz, the period of vibration is:
Period = 1/5.0 s
Period = 0.2 s
B. If the cart's mass is doubled while the spring constant remains unchanged, the frequency of vibration will not change. This is because frequency is dependent on the spring constant and the mass of the cart and not on the amplitude of the oscillation.
C. If the spring constant doubles while the cart's mass remains the same, the frequency of vibration will also double. This is because frequency is directly proportional to the square root of the spring constant. Therefore, doubling the spring constant would lead to an increase in the frequency of vibration by a factor of square root of 2.
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if a bullet has a mass of 0.013 (13 gram) and moves at 1800 m/s what is it's momentum
Answer:
23.4 kg m/s
Explanation:
p = mv = 0.013kg × 1800m/s = 23.4 Kg.m/s
Imagine that an object i falling through a long traight gla tube held vertical; air ha been removed
completely from the tube. The object doe not touch the wall of the tube. Will the object experience any
force of friction
No, the object will not experience any force of friction because there is no air or other medium in the tube to create friction against the object.
This is because friction is only possible when two objects are in contact with each other, or when an object is in contact with a medium like air or water. Since there is no air or other medium in the tube, there is nothing for the object to interact with. As a result, the object will fall through the tube without any external forces acting on it, such as friction. The motion of the object will be completely determined by the force of gravity and the object's inertia, and no other external forces will be present.
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A new planet is discovered with a radius that is 1/2 the radius of earth and 1/2 the mass of the earth. What is the acceleration due to gravity on this planet?
The acceleration due to gravity on this planet is 19.6 m/s².
What is acceleration?Acceleration is the rate at which the speed and direction of a moving object vary over time. A point or object going straight ahead is accelerated when it accelerates or decelerates. Even if the speed is constant, motion on a circle accelerates because the direction is always shifting. Both effects contribute to the acceleration of all other motions.
What is gravity?
In mechanics, gravity also known as gravitation is the constant force of attraction that pulls all things together. It has little impact on determining the intrinsic characteristics of common stuff because it is by far the weakest known force in nature.
Calculation:
The acceleration due to gravity on the earth's surface is given by
g = [tex]\frac{GM}{R^{2} }[/tex]
Now, Mp = [tex]\frac{M}{2}[/tex], Rp = [tex]\frac{R}{2}[/tex]
The acceleration due to gravity on the new planet is:
[tex]g_{p}[/tex] = [tex]\frac{GM_{p} }{R_{p} ^{2} }[/tex] = [tex]\frac{GM/2}{R^{2} /4^{} }[/tex] = 2g
[tex]g_{p}[/tex] = 2 × 9.8 = 19.6 m/s².
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a typical gps satellites orbit at an altitude of 2.0 x10^7 m. find (a) the orbital period, and (b) the orbital speed of such a satellite
the orbital period is 7200sec or 2hours and orbital speed is 7,27m/s
(a) The orbital period of a satellite is the time it takes for the satellite to make one full orbit around the Earth. To calculate the orbital period, we can use the equation: T = 2 * pi * (a^3/GM)^(1/2) where T is the orbital period, a is the semi-major axis of the orbit (which is equal to the altitude of the satellite), pi is approximately 3.14, G is the gravitational constant (approximately 6.67 x 10^-11 m^3/kgs^2), and M is the mass of the Earth (approximately 5.98 x 10^24 kg).Plugging in the given altitude of 2.0 x 10^7 m for a and the known values for pi, G, and M, we get:
T = 2 * pi * (2.0 x 10^7 m)^3/ (6.67 x 10^-11 m^3/kgs^2 * 5.98 x 10^24 kg)^(1/2)
Simplifying, we get:
T = 2 * pi * (8.0 x 10^21 m^3/ (4.03 x 10^34 kg*m^3/s^2))^(1/2)
T = 2 * pi * (1.98 x 10^13 s^2/kg)^(1/2)
T = 7200 sec (or 2 hours)
(b) The orbital speed is the distance traveled by the satellite in one hour. We can calculate the orbital speed using the equation v = 2πa/T
Plugging in the values of a and T we get :
v = 2π (2.0 x 10^7 m) / 7200 sec
v = 7,27 m/s
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A car moves in a straight line at 20.0 m/s for 8.00 miles, then at 30.0 m/s for another 8.00 miles. a. Is the car's average speed less than, greater than, or equal to 25.0 m/s
The average speed of the car is 24 m/s. The average speed of the car is therefore below 25.0 m/s.
What is speed ?The description of rapidity. a change in the location of an object in either direction or speed. How fast something is going is determined by the distance travelled and the time required to cover that distance. Speed is a scalar quantity since it just has an arrow-like direction and no magnitude.
What is distance ?The entire movement of an item, independent of direction, is called distance. Distance may be characterized as the quantity of ground covered, regardless of the starting or finishing points of an item.
distance (d) = 9 miles = 14.4841 km
d = 14484.1 m
1 miles = 1609.34 m
t₁= 14484.1/ 20
= 724.2 sec
t₂= 14484.1/ 30= 482.8 sec
total time ( t) = t+t
t= 724.2+ 482.8 = 1207 sec
Vavg = 2d/t= 2*14484.1/1207
Vavg = 24m/s
24< 25
lessthan 25m/s
car average speed (Vavg) = 24 m/s.
Therefore, the car average speed is 24 m/s.
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The capacitor charge Q exponentially decays to zero when the RELAY is thrown to position N.O.
O True
O False
The statement is false. The capacitor doesn't charge Q exponentially decays to zero when the RELAY is thrown to position N.O.
As a capacitor charges, its voltage also rise.
V = Q/C
where Q = charge, V = voltage and C = capacitance
If the circuit contains a battery, a resistor and a capacitor all connected in series, then the following are true.
The battery voltage is fixed. And the capacitor voltage is rising. This clearly means that the current through the resistor is dropping.
I = (Vbatt - Vcap)/R
Since the current is dropping, then the rate at which charge is deposited on one plate and removed from the other one continuously drops.
So the charging of the capacitor also slows down because of the rising voltage.
But here the rise in the voltage is slowing down because of the rate of charges that are accumulating and leaving continuously is slowing down.
The slower rise in voltage causes a further slowing in the rate of charge movement which further slows down the rise in voltage which causes an even slower rate of charge movement.
A capacitor is referred as an electrical device which stores electrical charge when it is connected across the source of potential difference.
The total charge that the capacitor can be stored when it is placed across a potential V is given by
Q=CV
where C is the capacitance of the capacitor.
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The half life of a radioactive substance is the time taken for the activity to halve. Use the graph to calculate the half life of the radioactive isotope.
Radioactive element which keeps on decaying over the time. Decay of radioactive element always comes under first order kinetics. Therefore the half life time of radioactive substance is 2seconds.
What is half life?Half life tells about the time at which the radioactive material decays to half of its initial concentration.
Mathematically,
half life time=0.693/ rate constant of the decay
The half life of a radioactive substance is the time taken for the activity to halve. Using the graph to calculate the half life of the radioactive isotope, we find that activity that is 3500 so, half of this activity is 17500 which is corresponding to time 2 seconds.
Therefore the half life time of radioactive substance is 2seconds.
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