(a) The initial kinetic energy (KE) of the automobile is 375,000 J
(b) The final KE will also be 375,000 J.
(c) The work done on the automobile is zero
What is the initial kinetic energy?The initial kinetic energy (KE) of the automobile can be found using the formula:
KE = 1/2mv²
where;
m is the mass of the automobile and v is its velocity.KE = 1/2 x 1200 kg x (25 m/s)²
KE = 375,000 J
The final KE of the automobile will be the same as the initial KE if the velocity remains constant. However, if there is a change in velocity, the final KE can be found using the same formula as above.
The change in KE can be found by subtracting the initial KE from the final KE, or by using the work-energy theorem:
ΔKE = W
where;
ΔKE is the change in kinetic energy and W is the work done.Assuming there is no external work done on the automobile, the change in KE will be zero.
Therefore, the final KE will also be 375,000 J.
The work done on the automobile can be found using the work-energy theorem:
W = ΔKE = 0 J (since there is no change in KE)
Therefore, the work done on the automobile is zero.
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From these measurements, compute the possible error in the volume.
Plugging in the values of the length and diameter, along with the error value, the error in the volume of the cylinder is approximately 1.27 cm³.
What is error in measurement?Error in measurement refers to the deviation or difference between the true or expected value and the measured value of a physical quantity. The presence of errors in measurement can affect the accuracy and precision of the results obtained.
To compute the possible error in the volume of the cylinder, we first need to calculate the volume of the cylinder using the measured values of its length and diameter:
V = πr²h
r = d/2 = 2.1/2 = 1.05 cm
V = π(1.05)²(8.9) = 31.79 cm³
Now, we need to determine the possible error in the volume, which can be calculated using the formula:
ΔV = V × √[(Δd/d)² + (Δh/h)²]
where Δd and Δh are the uncertainties in the diameter and length measurements, respectively. Substituting the given values, we get:
ΔV = 31.79 × √[(0.1/2.1)² + (0.1/8.9)²] = 1.27 cm³ (approx.)
Therefore, the possible error in the volume of the cylinder is approximately 1.27 cm³.
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A similar device includes a transformer so that an MP3 player can also be charged. The primary coil has 300 turns.
(a) How many turns are needed in the secondary winding if the voltage is stepped up from 6.2 V to 15.5 V?
(b) Given that the current in the primary winding is 10 mA, what power is transmitted to the secondary windings if the transformer is 77% efficient?
The secondary coil needs 120 turns.The power transmitted to the secondary winding is 0.155 W.
How does the voltage change between the primary and secondary coil in a transformer?A transformer works by using electromagnetic induction to transfer electrical energy between two circuits. The voltage changes between the primary and secondary coil based on the ratio of the number of turns in each coil. In a step-up transformer, the voltage is increased from the primary to the secondary coil, while in a step-down transformer, the voltage is decreased.
Transformers are commonly used in electronic devices to convert voltage levels, isolate circuits, and match impedances. They are often used in power supplies to step down the voltage from the wall outlet to a level that can be used by the device. They are also used in audio amplifiers to match the impedance of the output to the speaker, and in radio and television receivers to tune in to different frequencies.
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The units of voltage are
Oohms, amps, volts
Oamps, volts, ohms
Ovolts, ohms, amps
Ovolts, amps, ohms
of current are
and of resistance are
Answer:24 volts ÷ 4 amps = 6 ohms
Explanation:
We know that the Ohm's law has given the relationship between the current, voltage and the resistance of the wire. Mathematically, it can be written as :
Where
I is the current
R is the resistance
If current flowing is 4 amps and voltage is 24 volts. The formula to find the resistance will be :
R = 6 Ohms
Hence, the correct option is (d) " 24 volts ÷ 4 amps = 6 ohms ".
A 300 g football is kicked with an initial velocity of 140 m/s in a direction that
makes a 30° angle with the horizon. Find the peak height of the football.
Answer:
Explanation:
Assuming that air resistance is negligible, we can use the following kinematic equations to solve for the peak height:
v_f^2 = v_i^2 + 2ad
where v_f = 0 m/s (at the peak height) and a = -9.8 m/s^2 (acceleration due to gravity)
and
d = v_i t + (1/2)at^2
where d is the displacement or the peak height we want to find, v_i is the initial velocity, t is the time it takes to reach the peak height.
First, we need to resolve the initial velocity into its vertical and horizontal components:
v_i_x = v_i cos(30°) = 121.1 m/s
v_i_y = v_i sin(30°) = 70.0 m/s
Next, we can use the vertical component of the initial velocity to find the time it takes to reach the peak height:
v_f = v_i_y + at
0 m/s = 70.0 m/s + (-9.8 m/s^2)t
t = 7.14 s
Finally, we can use the time we found and the kinematic equation for displacement to find the peak height:
d = v_i_y t + (1/2)at^2
d = (70.0 m/s)(7.14 s) + (1/2)(-9.8 m/s^2)(7.14 s)^2
d = 247.5 m
Therefore, the peak height of the football is 247.5 meters.
Work Energy Theorem Question: You apply 50 N to a 10 kg object to cause it to move from rest to 2.5 m/s. What distance was the object moved?
Answer:
0.625 meters
Explanation:
We can use the work-energy that the work done on an object is equal to the change in its kinetic energy:
Work = ΔK = Kf - Ki
Where:
Work is the work done on the object
ΔK is the change in kinetic energy of the object
Kf is the final kinetic energy of the object
Ki is the initial kinetic energy of the object (which is zero since the object is at rest)
The work done on the object is equal to the force applied to the object multiplied by the distance over which the force is applied:
Work = F × d
Where:
F is the force applied to the object (50 N)
d is the distance over which the force is applied (unknown)
So we can write:
F × d = Kf - Ki
Substituting the given values:
50 N × d = 1/2 × 10 kg × (2.5 m/s)^2 - 0
Simplifying:
50 N × d = 31.25 J
Solving for d:
d = 31.25 J / 50 N = 0.625 m
Therefore, the object was moved a distance of 0.625 meters.
please rate
Explain how a balloon is able to keep its shape?
Answer:
It depends on how they are made.
Explanation:
Rubber balloons are not always spherical in shape. When filled with air, the inflation forms a balance between the balloon material, including its shape and thickness and its elasticity and the pressure of the air. That’s what determines its shape. Although a sphere is often the shape, it could be tubular, offset, and most other shapes.
What is the defining property of an mechanical wave?
A. It travels by compressing particles.
B. It travels up and down.
C. It does not need a medium to travel.
D. It needs a medium to travel.
Answer: D. It needs a medium to travel.
Explanation:
One way to categorize waves is on the basis of the direction of movement of the individual particles of the medium relative to the direction that the waves travel. Categorizing waves on this basis leads to three notable categories: transverse waves, longitudinal waves, and surface waves.
The driver of a car with a total of 1800 kg mass is traveling at 23 m/s when he slams on the brakes, locking the wheels on the dry pavement. The coefficient of kinetic friction between rubber and dry concrete is typically 0.7. How far would the car travel if were going twice as fast
Answer:
To solve this problem, we can use the formula:
d = (v^2)/(2μg)
d = distance traveled
v = speed of the car
μ = coefficient of kinetic friction
g = acceleration due to gravity
First, let's calculate the distance traveled when the car is traveling at 23 m/s:
d = (23^2)/(2*0.7*9.81) ≈ 67.97 meters
Now, let's calculate the distance traveled when the car is going twice as fast (46 m/s):
d = (46^2)/(2*0.7*9.81) ≈ 271.88 meters
Therefore, the car would travel approximately 271.88 meters if it were going twice as fast.
What was the angle of application of the force of 35 if on a distance of 15 the work of 350 was done?
Dish Network sent a satellite into orbit around 36000 km above the Earth's surface. What is the speed of the Satellite in miles per hour?
G=6.67 x 10^-11
M Earth = 5.98 x 10^24 kg
R Earth = 6.37 x 10^6 m
A. 306889 mi/hr
B. 6,864.38 mi/hr
C. 6.86491 mi/hr
D. 9.8mi/hr
Answer:
Explanation:
First, we need to use the formula for the speed of an object in circular orbit:
v = sqrt(GM/R)
where G is the gravitational constant, M is the mass of the Earth, R is the distance between the center of the Earth and the satellite.
Converting the units to meters and kilograms:
G = 6.67 × 10^-11 m^3/kg s^2
M = 5.98 × 10^24 kg
R = (36000 + 6.37 × 10^6) × 1000 = 4.23 × 10^7 m
Plugging in the values:
v = sqrt((6.67 × 10^-11) × (5.98 × 10^24) / (4.23 × 10^7))
v ≈ 3075.58 m/s
Finally, we can convert this to miles per hour:
v = 3075.58 m/s x (3600 s/hr) / (1609.34 m/mi) = 6873.18 mi/hr
Therefore, the answer is option A. 306889 mi/hr is incorrect.
Match these items.
changes mechanical energy to heat energy, force x distance, rubbing energy ,using energy wisely, can cause heat pollution
work is done
collision
friction
stewardship
nuclear
energy
Mechanical energy to heat energy is collision,force x distance is work done,rubbing energy friction, stewardship is using energy wisely and nuclear energy can cause heat pollution.
EnergyThere are six different types of energy: chemical, electrical, radiant, mechanical, thermal, and nuclear. Other forms including electrochemical, auditory, electromagnetic, and others might be described in other study.Kinetic energy is the term for the energy that drives motion. Kinetic energy includes electrical and mechanical energy.Energy is the ability to conduct work in physics. It may exist in potential, kinetic, thermal, electrical, chemical, nuclear, or other other forms. Moreover, there is heat and work, which is energy moving from one body to another.For more information on energy kindly visit to
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How could you use the game of baseball to explain the difference between
inertia and momentum?
Explanation:
Inertia refers to the tendency of an object to resist changes in its motion. In baseball terms, a baseball that is at rest on the ground has a high level of inertia because it is resistant to moving until an external force, such as a player's bat, acts on it.
Momentum, on the other hand, is the product of an object's mass and velocity and refers to the quantity of motion that an object possesses. In baseball terms, a baseball that is moving at a high velocity, such as when it is hit by a bat, has a high level of momentum.
To illustrate the difference between inertia and momentum in baseball, consider the scenario of a baseball that is hit by a bat. Before the bat hits the ball, the ball is at rest and has a high level of inertia. However, once the bat hits the ball, the ball gains momentum and begins to move. As the ball moves, it continues to possess momentum, but its inertia gradually decreases as it encounters external forces, such as air resistance and friction from the ground, which act to slow it down.
Which material would you choose to make the handrails of the playhouse? Use the data to explain your reasoning.
Answer:
Explanation:
To choose a material for the handrails of the playhouse, we need to consider its strength and durability. One option could be stainless steel, which has a high tensile strength and is resistant to corrosion and weathering. Another option could be treated wood, which is also strong and can be treated to resist moisture and insects. Ultimately, the choice would depend on factors such as cost, aesthetics, and availability of materials.
A block of mass m1=3.0kg rests on a frictionless horizontal surface. A second block of m2=2.0kg hangs from an ideal cord of negligible mass that runs over an ideal pulley and then is connected to the first block . the blocks are released from rest . determine the displacement of the velocityA block of mass m1=3.0kg rests on a frictionless horizontal surface. A second block of m2=2.0kg hangs from an ideal cord of negligible mass that runs over an ideal pulley and then is connected to the first block . the blocks are released from rest . Determine how far has block 1 moved during the 1.2-s interval?
A) 13.4 m
B) 2.1 m
C) 28.2m
D) 7.6m
The answer is:
D. 7.6m
why the ocean near Christchurch is a different temperature than we’d expect for its latitude
Why the ocean near Christchurch is a different temperature than we'd expect for its latitude (distance from the equator)? Water moving from the equator is warmer than would be expected based on latitude, and so is warmer than the air it passes.
Changes to prevailing winds affect ocean currents. Changes to ocean currents affect how much energy is brought to (or taken away from) a location. In El Niño years, the prevailing winds that normally drive a warm current from the Equator past New Zealand are disrupted and may stop or even reverse.
waves are generated in a rope of length 6m. What is the speed of the wave if its period is 25.m
The speed of the wave would be0.48 m/s.
Speed of a waveThe speed of a wave is given by the formula:
v = λ/T
where v is the wave speed, λ (lambda) is the wavelength, and T is the period.
To solve this problem, we need to know the wavelength of the wave. We can find the wavelength using the formula:
λ = 2L
where L is the length of the rope. Substituting L = 6 m, we get:
λ = 2 × 6 m = 12 m
Now we can use the formula for wave speed:
v = λ/T
Substituting λ = 12 m and T = 25 s, we get:
v = 12 m/25 s = 0.48 m/s
Therefore, the speed of the wave is 0.48 m/s.
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A rocket takes off from a space station, where there is no gravity other than the negligible gravity due to the space station, and reaches a speed of 110 m/s in 10.0 s. If the exhaust speed is 1,600 m/s and the mass of fuel burned is 118 kg, what was the initial mass (in kg) of the rocket?
The initial mass of the rocket was 106 kg.
What is the initial mass of the rocket?We can use the principle of conservation of momentum to solve this problem.
The momentum of the rocket before takeoff is zero, since it is at rest, and the momentum after takeoff is the product of the mass of the rocket and its velocity.
However, during the takeoff, the rocket ejects a mass of fuel at a certain velocity, which creates a backward force (thrust) that propels the rocket forward.
This thrust can be calculated using the equation:
Thrust = (mass flow rate) x (exhaust velocity)
mass flow rate = (mass of fuel burned) / (burn time)
The mass of the rocket at any given time can be calculated using the equation:
mass = (initial mass) - (mass of fuel burned)
Using these equations, we can solve for the initial mass of the rocket:
Calculate the thrust:
Thrust = (118 kg / 10.0 s) x 1600 m/s = 1,888 N
Calculate the mass of the rocket at the end of the burn:
mass(end) = (initial mass) - (mass of fuel burned) = (initial mass) - 118 kg
Use the principle of conservation of momentum to find the initial mass:
momentum before = momentum after
0 = (mass(end) + 118 kg) x 110 m/s
mass(end) = -118 kg / 110 m/s = -1.07 kg/s
mass(end) = (initial mass) - 118 kg
(initial mass) = mass(end) + 118 kg
(initial mass) = (-1.07 kg/s x 10.0 s) + 118 kg
(initial mass) = 106 kg
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How long would it take a car from rest and acceleration in a straight line ar 5 metres per sec to cover a dis of 200
Answer:
Explanation:
To solve this problem, we can use the following kinematic equation:
d = 1/2at^2 + vt
where d is the distance, a is the acceleration, t is the time, and v is the initial velocity.
We know that the car is starting from rest, so v = 0. We also know that the acceleration is 5 m/s^2 and the distance to be covered is 200 m. Plugging these values into the equation, we get:
200 = 1/2(5)t^2 + 0
Simplifying:
t^2 = 80
Taking the square root of both sides:
t = 8.9 s
Therefore, it would take the car approximately 8.9 seconds to cover a distance of 200 meters from rest with an acceleration of 5 meters per second squared.
Why is it important to assess your fitness level?
Assessing your fitness level is important because it help in tracking your progress and determine if you are making improvements. Regular assessments can help you identify areas where you may need to make adjustments to your fitness routine to achieve your goals. By assessing fitness level, you can identify areas where you may be weaker or less flexible. This information can help you design a fitness routine that addresses these areas and reduces our risk of injury.
Regular physical activity and exercise can improve overall health and reduce the risk of chronic diseases such as heart disease, diabetes, and obesity. By understanding your fitness level, you can design an exercise routine that helps you achieve optimal health and wellness.
Gas pressure is defined as
Select one:
O a. mass per unit area
O b.
O c. force per unit area
O d. force per unit volume
acceleration per unit volume
Answer: b. force per unit area.
Explanation:
You leave Fort worth ,Texas,at 2:41 p.m. and arrive in Dallas at 3:23 p.m. , covering a distance of 58km. what is your average speed in metres per second ?
Answer:
Explanation:
The time taken to travel from Fort Worth to Dallas is:
t = 3:23 pm - 2:41 pm = 42 minutes = 0.7 hours
The distance covered is:
d = 58 km
The average speed is:
v = d/t = 58 km / 0.7 hours = 82.86 km/h
To convert km/h to m/s, we can use the conversion factor:
1 km/h = 0.2778 m/s
Therefore, the average speed in m/s is:
v = 82.86 km/h × 0.2778 m/s/km = 23.06 m/s (rounded to two decimal places)
So the average speed is 23.06 m/s.
Mary walked north from her home to Sheila's home, which is 4.0 kilometers away. Then she turned right and walked another 3.0 kilometers to the supermarket, which is 5.0 kilometers from her own home. She walked the total distance in 1.5 hours. What were her average speed and average velocity?
A.
Her average speed was about 4.6 km/hr, and her average velocity was about 3.3 km/hr.
B.
Her average speed was about 3.3 km/hr, and her average velocity was about 4.6 km/hr.
C.
Her average speed was about 3.3 km/hr, and her average velocity was 0 km/hr.
D.
Her average speed was 0 km/hr, and her average velocity was about 4.6 km/hr.
Her average speed was about 4.6 km/hr, and her average velocity was about 3.3 km/hr.
The entire distance travelled divided by the total time taken is the definition of average speed. In this case, the total distance travelled was 7.0 km, and the total time taken was 1.5 hours. Hence, the average speed can be determined as follows:
Average Speed = [tex]\frac{7.0 km }{ 1.5 \ hours }= 4.6 km/hr[/tex]
The displacement divided by the whole time travelled is the average velocity. In this case, the displacement was 3.0 km (from Mary's home to Sheila's home), and the total time taken was 1.5 hours.The average velocity can therefore be determined as follows:
Average Velocity = [tex]\frac{3.0 km }{1.5 \ hours} = 3.3 km/hr[/tex]
Therefore,Her average velocity was roughly 3.3 km/hr, and her average speed was roughly 4.6 km/hr.
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460miles per hour with the wind nd 420 per hour gainst the wind
The speed of the wind is 20 miles per hour.
To solve this problem, we can use the formula:
Speed = Distance/Time
Let's assume that the speed of the wind is x miles per hour.
With the wind, the plane travels at a speed of 460 miles per hour. This means that its speed relative to the ground is the sum of its airspeed and the speed of the wind:
460 = Airspeed + x
Against the wind, the plane travels at a speed of 420 miles per hour. This means that its speed relative to the ground is the difference between its airspeed and the speed of the wind:
420 = Airspeed - x
We can solve this system of equations to find the airspeed of the plane:
460 = Airspeed + x
420 = Airspeed - x
Adding the two equations gives:
880 = 2Airspeed
Dividing both sides by 2 gives:
Airspeed = 440 miles per hour
Now that we know the airspeed of the plane, we can find the speed of the wind by substituting this value into one of the equations we obtained earlier:
460 = Airspeed + x
460 = 440 + x
x = 20
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A metal filament Lamp rated at 750w, 100v into be connected in series with a capacitor across a 230v, 60hz supply. Calculate the capacitance required
Answer : 0.00885 farads or 8.85 microfarads
Explanation: To calculate the capacitance required, we can use the following formula:
C = 1 / [2 * pi * f * ((V^2 - Vlamp^2)/P)]
where:
C = capacitance in farads (F)
pi = 3.14159...
f = frequency in hertz (Hz)
V = voltage in volts (V)
P = power in watts (W)
Vlamp = voltage of the lamp in volts (V)
Using the given values, we have:
C = 1 / [2 * pi * 60 * ((230^2 - 100^2)/750)]
C = 1 / [2 * 3.14159 * 60 * ((230^2 - 100^2)/750)]
C = 1 / [113.09724]
C = 0.00885 farads (F)
Therefore, the capacitance required is approximately 0.00885 farads or 8.85 microfarads.
Which correctly describes a different evolutionary stage of a star like the sun
A) it’s forms from a cold, dusty molecular cloud
B) During a yellow giant stage, it burns carbon in its core and helium in the shell surrounding the core.
C) After leaving the main sequence, its core is stable due to electron degeneracy
D) It becomes a white dwarf after exploding as a supernova
E)During a red giant stage, its core contracts and cools
The statement that correctly defines an evolutionary stage of a star like the sun is that after leaving the main sequence, its core is stable due to electron degeneracy. That is option C.
What are the stage of life cycle of a star?The stages of the life cycle of a star include the following:
Giant Gas CloudProtostarT-Tauri PhaseMain SequenceRed GiantThe Fusion of Heavier ElementsSupernovae and Planetary NebulaeThe evolutionary stage is also called the main sequence stage of the life cycle of the star.
In this stage, the core temperature reaches the point for the fusion to occur whereby the protons of hydrogen are converted into atoms of helium. This leads to the stability of the core of the newly formed start due to electron degeneracy.
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1. A 8.2 kg mass hanging from a spring scale is slowly lowered onto a vertical spring.
A) What does the spring scale read just before the mass touches the lower spring?
B) The scale reads 14 N when the lower spring has been compressed by 2.4 cm . What is the value of the spring constant for the lower spring?
C) At what compression length will the scale read zero?
The spring scale read just before the mass touches the lower spring is 80.36N, the spring constant for the lower spring is 2765N/m and at 2.9cm length the scale will read zero.
Given the mass of spring = 8.2kg
The force exerted for compressing of spring = 14N
The compression in spring = 2.4cm = 0.024m
(A.) Initially the spring scale reads only the weight of the mass = mg
W = 8.2 * 9.8 = 80.36N
(B) Let the value of spring constant = k
The net force exerted so that the scale reads(F') = 80.36N - 14 = 66.36N
We know that according to Hooke's law the force exerted on spring F = kx such that:
F' = kx then:
66.36 = k * 0.024
k = 66.36/0.024 = 2765N/m
(C) the compression where scale reads zero = x'
The scale reads zero when the restoring force equals to the weight of the mass then the scale reads zero such that:
x' = 80.36/2765 = 0.029m = 2.9cm
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HELPPPP LATE HOMEWORK DUE TODAY
If F₁ has a greater magnitude than F₂, the box will accelerate backward because the net force is in the backward direction (1st option)
How do i know which direction the box will move to?To obtain the direction in which the box will move, we shall determine the net force acting on the box. This is illustrated below:
Assumption:
Magnitude of force 1 (F₁) = 40 NMagnitude of force 2 (F₂) = 25 NNet force (F) =?Net force = Magnitude of force 1 (F₁) - Magnitude of force 2 (F₂)
Net force = F₁ - F₂
Net force = 40 - 25
Net force = 15 N backward
From the above illustration, we can see that the net force is 15 N backward.
Thus, we can conclude from the box will accelerate backward (1st option)
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What is the momentum of a 2.3 kg ball rolling at 6 m/s?
Show your work
Answer:
13.8 (kgm)/s
Explanation:
p(momentum) = m (mass) * v (velocity)
p= 2.3 * 6
p = 13.8
A soccer player kicks a ball of mass 0.500 kg toward the goal.The ball hits the crossbar at a height of 2.6 m with a speed of 15.0m/s. Suppose the ball was at rest on the ground before it was kicked. Use g = 9.80 m/s.
Answer:
The speed of the ball just before it hits the crossbar is 7.22 m/s.
Explanation:
We can use the conservation of energy to solve this problem.
At the moment the player kicks the ball, the ball has only kinetic energy, since it was at rest on the ground before being kicked. When the ball hits the crossbar, it has both kinetic energy and potential energy, since it is at a height above the ground. We can set the initial kinetic energy equal to the sum of the final kinetic and potential energy:
(1/2)mv^2 = mgh
where:
m = mass of the ball (0.500 kg)
v = initial speed of the ball (15.0 m/s)
g = acceleration due to gravity (9.80 m/s^2)
h = height of the crossbar above the ground (2.6 m)
We want to solve for the speed of the ball just before it hits the crossbar, which we can do by rearranging the equation:
v = sqrt(2gh)
v = sqrt(29.802.6) = 7.22 m/s (rounded to two decimal places
A 208g sample of sodium-24 decays to 13.0g of sodium-24 within 60.0 hours. What is the half life of this radioactivity isotope?
Answer:
15 hours
Explanation:
formula: f(a) = a(0.5)^(T/t)
fill in known values: 13=208(0.5)^(60/t)
use natural log to isolate t: ln(13/208)=ln(0.5)(60/t)
solve for t: t=15