half-life questionnnnn:

Half-life Questionnnnn:

Answers

Answer 1
120 and 150 and 180 and 210

Related Questions

a heat engine is a device that uses to produce useful work

Answers

A heat engine is a device that uses to produce useful work.

Definition - a device for producing motive power from heat, such as a gasoline engine or steam engine.

So..

If this is a true or false question.. Your answer is:

TRUE

Answer:

HEAT

Explanation:

Which car is experiencing negative acceleration?
A. a car sitting at a red light
B. a car slowing down as it approaches a red light
C. a car driving in a circle at a constant speed
D. a car changing its speed from 0 km/hr to 10 km/hr

Answers

Answer:B

Explanation:

Answer: b

Explanation: b as it slows down and decelerates


Scenario 3: You are driving through a rain storm talking to your family but you can only hear every other word. What 2 medias are the waves passing in this scenario?

Answers

The sound waves are passing through the sound of the rain and the air around you

A ball is launched from ground level at 30 m/s at an angle of 35° above the horizontal. how far does it go before it is at ground level again

Answers

Answer:

Explanation:

Ignoring air resistance

Initial vertical velocity is 30sin35 = 17.2 m/s

Gravity reduces this velocity to zero in a time of

t = v/g =17.2 / 9.8 = 1.755 s

it takes the same time to come back down to ground level for a total flight time of 2(1.755) = 3.51 s

The horizontal velocity is 30cos35 = 24.57 m/s

the distance traveled horizontally is

d = vt = 24.57(3.51) = 86.298... = 86 m

A student removed a wool hat from her head. Her hair stood up from static electricity. What did her hat do to cause this

Answers

Answer:

A student removed a wool hat from her head. Her hair stood up from static electricity. What did her hat do to cause this? ... Yes, the motor would run faster because the increased electrical force increases the magnetic force in the motor.

A student removed the wool from her head due to the static charge of electricity, it is caused.

What is charge?

A difference in electric charge within, on the surface of, or between two materials results in static electricity. Until it can be expelled through an electrical discharge or current, the charge stays. In contrast to current electricity, which transmits energy by letting an electric charge flow through a conductor or a space, static electricity does not transport energy.

When two surfaces come into contact, wear, and separate from one another when at least a single surfaces has a good resistance to electric current, a static electrostatic attraction can be produced. Because individuals can feel, hear, and even see a spark when the extra charge is neutralized when placed close to a powerful electrical conductor, most people are familiar with static electricity's effects.

To know more about charge :

https://brainly.com/question/19886264

#SPJ5

2. An object is falling under gravity with terminal velocity. What is happening to its speed?
A. It is decreasing to a lower value.
B. It is increasing
C. It is decreasing to zero.
D. It is staying constant.

Answers

Answer:

the speed of the object has become constant.

Explanation:

At terminal velocity, air resistance equals in magnitude the weight of the falling object. Because the two are oppositely directed forces, the total force on the object is zero, and the speed of the object has become constant.

The answer is B because of the acceleration

An action that has the ability to change an object’s state of motion is

Answers

Answer:

An unbalanced force

Explanation:

Answer:

Force

Explanation:

Trust me

A section of a rollercoaster is shown below. If the 17,500 kg rollercoaster momentarily comes to rest at point A, where it is 19 m in the air, how fast is it going at point D?

Answers

Answer:

Explanation:

Impossible to say without knowing how high point D is.

If we ignore friction, the energy converted from potential energy will exist as kinetic energy.

let d be the height in meters of point D "in the air"

mg(19 - d) = ½mv²

m is common so divides out

g(19 - d) = ½v²

v = √(2g(19 - d))

no sense in making g any more precise than the height. g = 9.8

v = √(2(9.8)(19 - d))

v = √(19.6(19 - d))

How much potential energy does an 8 kg flower pot hanging 5 m above the ground have

Answers

Answer:

Explanation:

Relative to ground level it has

PE = mgh = 8(10)(5) = 400 J

PE = mgh => 8x5x9.81 => PE = 392.4 N

3. A ball is dropped from the roof of a building 55 meters tall. What is the approximate time of fall?
(Neglect air resistance and round to 2 decimal places).

Answers

Answer:

3.35 seconds

Explanation:

Use one of the equations of accelerated motion:

Δd = v1Δt+1/2aΔt^2

and rearrange for Δt which is time

Δt = √(2Δd)/a

now we can substitute in the values

a= 9.8 (acceleration due to gravity) and Δd= 55 as that is the height of the building

Δt = √(2*55)/9.8

Δt = 3.3503s

Four balls with different masses are dropped from the heights shown. Air resistance may be ignored. Which ball has the greatest average speed?

Answers

Answer:

The one falling from the greatest height will have the greatest speed.

h = 1/2 g t^2        time for ball to fall distance h

h2 / h1 = t2^2 / t1^2       dividing equations

h2 / t2^2 = h1 / t1^2

Let v be the average speed (v2 = h2 / t2)

1 / t2 * v2 = 1 / t1 * v1

v2 / v1 = t2 / t1      the one taking the longest to fall has the greater av. speed

Check:

h4 / h1 = t4^2 / t1^2     or

t4 / t1 = (h4 / h1)^1/2

In this case t4 / t1 = (4 / 1)^1/2 = 2  or twice the average speed

t1 = (2 h / g)^1/2 = .2^1/2 = .447       using g = 10

t4 = (2 h / g)^1/2 = .8^1/2 = .894

v1 = 1 / .447 = 2.24 m/s average speed

v4 = 4 / .894 = 4.47    or twice the average speed

Which is true of gamma radiation? O A. It increases the number of protons. O B. It is the heaviest of the three types. O C. It does not cause transmutation. O D. It has a positive charge.

Answers

Answer:  Your answer Is A)

Explanation:    

Its direction of deflection shows it possitively charged

It brings one element into another by bombardment(transmutation)

Which is an electromagnetic wave A. The waves that heat a cup of water in a microwave oven B. A flag waving in the wind C. Turning on a flashlight D.The changes in the air that result from blowing a horn

Answers

Answer:

The answer would be A. The waves that heat a cup of water in a microwave oven

In a police ballistics test, 2.00-g bullet traveling at 700 m/s suddenly hits and becomes embedded in a stationary 5.00-kg wood block. What is the speed of the block immediately after the bullet has stopped moving relative to the block

Answers

Answer:

Here we use the conservation of momentum theorem.

m stands for mass, and v stands for velocity. The numbers refer to the respective objects.

m1v1 + m2v2 = m1vf1 + m2vf2

Since the equation is perfectly inelastic, the final velocity of both masses is the same. Let’s account for this in our formula.

m1v1 + m2v2 = vf(m1 + m2)

Let’s substitute in our givens.

(0.002 kg)(700 m/s) + (5 kg)(0 m/s) = vf(0.002 kg + 5 kg)

I assume you are proficient in algebra I, so I will not include the steps to simplify this equation.

Note that I have considered the bullet’s velocity to be in the positive direction,

The answer is vf = 0.280 m/s

A 5 kilograms bowling ball is dropped out a window. It hits the ground, and bounces upward. The velocity change of the ball is noted to be 15 m/s downward and 12 m/s upward. What is the contact time for the ball if the force applied on the ball from the ground is equal to 10 N?

Answers

Answer:

13.5

Explanation:

Mass: 5kg

Initial Velocity: -15

Final Velocity: 12

Force: 10

We can use the equation: Vf = Vi + at

We need to find acceleration, and we can use the equation, F=ma,

We have mass and the force so it would look like this, 10=5a, and 5 times 2 would equal 10, so acceleration would be 2.

Now we have all the variables to find time.

Back to Vf = Vi + at, plug the numbers in, 12 = -15 + 2(t)

Plugging them in into desmos gives 13.5 for time.

I need a short answer ?

Answers

Answer:

Explanation:

7a) t = d/v = 100/45cos14.5 = 2.29533...= 2.30 s

7b) h = ½(9.81)(2.29533/2)² = 6.46056... = 6.45 m

  or

  h = (45sin14.5)² / (2(9.81)) = 6.47 m

which rounds to the same 6.5 m when limiting to the two significant digits of the initial velocity.

A 200-kg, 2.0-m-radius, merry-go-round in the shape of a flat, uniform, circular disk parallel to level ground is rotating at 1.2 cycles/second about an axis through its center of mass and perpendicular to the ground. A 50-kg boy jumps onto the edge of the merry-go round and lands at a fixed point. What is the angular velocity of the merry-go-round after the boy lands on it

Answers

Answer:

Explanation:

Conservation of angular momentum.

Disk            I = ½MR²

Point mass I = mR²  (boy)

Initial angular momentum

L₀ = Iω = ½MR²ω₀

Final angular momentum

L₁ = Iω = (½MR² + mR²)ω₁

as momentum is conserved, these are equal

(½MR² + mR²)ω₁ = ½MR²ω₀

                       ω₁ = ω₀(½MR²/ (½MR² + mR²))

                       ω₁ = ω₀(½M/ (½M + m))

                       ω₁ = 1.2(½(200)/ (½(200) + 50))

                       ω₁ = 1.2(⅔)

                      ω₁ = 0.8 cycles/second or 0.8(2π) = 1.6π rad/s

4 points
This machine has a sharp edge and helps spread or cut something

Answers

Knife
Has a sharp edge and can cut bread or fruit and can spread butter or jam

How do I measure the drag of a paper airplane?

Answers

Answer:

hmmmmm ill get back later

Explanation:

Question 4 of 10
What is thermodynamics?
A. The movement of matter
B. The flow of fluids
C. The movement of particles
D. The flow of energy, heat, and work
SUBMIT

Answers

Answer:

Explanation:

D.

Thermodynamics is the study of  how different   types of energy is transferred through the  chemical systems

Answer: Thermodynamics is the flow of energy, heat, and work.

Explanation: This is seen in the formula for the first law of thermodynamics,  U = Q - W, or “The change of the internal energy of a system (U) is equal to the heat absorbed (Q) minus the work done by that system (W).”

what torque required stopping awheel of moment of inertia 6 × 10^-3kgm2 from speed of 40rad/s in 20 sec.​

Answers

solution:

the formula is T = F * r * sin(theta) so just input the numbers and solve it.

Explanation:

Torque is the twisting force that tends to cause rotation. The point where the object rotates is known as the axis of rotation. Mathematically, torque can be written as T = F * r * sin(theta), and it has units of Newton-meters

Which of the following waves DO NOT require a medium to travel?

Answers

Answer:

hey man, think you forgot to put the questions

How might "Roller Coaster Physics" have been different if the author's purpose had been to warn
readers of the dangers of roller coasters?
Use at least two details from the passage to support your answer.

Answers

Answer: The answer is hupa loopa

Explanation:

A container holds 192 g of oxygen gas at a pressure of 8.00 atm.
How much heat Q is required to increase the temperature by
145 °C at constant volume?

Answers

The quantity of heat (Q) that is required to increase the temperature at constant volume is 18,082.95 Joules.

Given the following data:

Mass of oxygen gas = 192 gPressure = 8.00 atmTemperature = 145°C

Scientific data:

Ideal gas constant, R = 8.314 J/molKMolar mass of oxygen gas = 32 g/mol.

To determine the quantity of heat (Q) that is required to increase the temperature at constant volume:

First of all, we would find the number of moles of oxygen gas.

[tex]Number\;of\;moles = \frac{mass}{molar\;mass}\\\\Number\;of\;moles = \frac{192}{32}[/tex]

Number of moles = 6 moles.

At constant volume, the heat capacity for a diatomic gas is given by:

[tex]C_v = \frac{5}{2} R\\\\C_v =\frac{5}{2} \times 8.314[/tex]

Heat capacity = 20.785 J/molK.

At constant volume, the quantity of heat (Q) is given by this formula:

[tex]Q = nC_v \Delta T\\\\Q=6 \times 20.785 \times 145[/tex]

Quantity of heat (Q) = 18,082.95 Joules

Note: [tex]\Delta T[/tex] = 145°C = 145 K (since the difference is the same).

Read more on heat capacity here: https://brainly.com/question/11150071

The primary evidence that has led astronomers to conclude that the expansion of the universe is accelerating comes from __________.

Answers

The Universe is often studied by Scientist. The primary form of evidence that has led astronomers to conclude that the expansion of the universe is accelerating is the Observations of white dwarf supernovae.

There was the discovery of the faintness of high-redshift Type I supernovae by a team of scientist which showed that the expansion of the universe is accelerating.

The key evidence for that made scientist to talk about the expansion of the universe is accelerating comes from viewing and studying of white dwarf supernovae. It has been found that most distant stars all orbit at approximate speed as stars found about 30,000 light-years from their center.

Learn more about  white dwarf from

https://brainly.com/question/12175185

HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!pls

Answers

I think this is the solution:

1: U-1, F,-4
2: Na-6, Mo-1, O-4
3: Bi-1, O-1, C-1, I-1
4: In-9, N-1
5: N-2, H-4, S-1, C-1
6: Ge- 15, N-4
7: N-1, H-4, C-1, I-1, O-3
8: H-7, F-1
9: N-1, O-5, H-1, S-1
10: H-8
11: Nb-1, O-1, C-1, I-3
12: C-3, F-3, S-1, O-3, H-1
13: Ag-1, C-1, N-1, O-1
14: Pb-6, H-1, As-1, O-4

"A soccer ball is kicked horizontally off a 22 m high hill and lands a distance of 35 m from the edge of the hill." Which variable is 35 m? *

Answers

Answer:Let’s assume that, after the soccer ball is kicked and moves through its trajectory, it first makes contact with level ground a horizontal distance of 35 meters from where it was kicked. Let’s also assume that we can neglect air resistance. The time, t, that the soccer ball is in the air until it first contacts the ground can be found from the equation h = (1/2)gt^2 which can be rewritten as t = sqrt(2h/g) where h is the vertical distance the ball falls which is the height of the hill since the ball was kicked horizontally, and g is the acceleration of gravity which is 9.8 m/s^2. So t = sqrt(2(22)/9.8) = 2.12 seconds. In that time, the ball travelled 35 meters so its horizontal velocity was 35 meters/2.12 seconds = 16.5 meters/second.

Explanation:

A person sitting in a chair with wheels stands up, causing the chair to roll backward across the floor. The momentum of the chair

a. was zero while stationary and increased when the person stood.

b. was greatest while the person sat in the chair.

c. remained the same.

d. was zero when the person got out of the chair and increased while the person sat.​

Answers

Answer:

a. was zero while stationary and increased when the person stood.

Explanation:

momentum is mass times velocity.

initial velocity was zero

final velocity was NOT zero.

Identify the type of chemical reaction:

CaCO3 -->CaO + CO2

Answers

Explanation:

decomposition reaction.....

Answer:

caco₃--cao+co₂

calcium oxide + carbon die oxide gives us calcium carbonate

this is the reaction of Acidic oxide(cao) and Basic oxide (co₂) to form salt.


Challenge
Marks: 1
How much energy is transferred by a 500 watt heater that is on for 2
minutes?

Answers

Answer:

Explanation:

500 W = 500 J/s

500 J/s(2 min(60 s/min) = 60000 J

Other Questions
What is the distance between points A and B?1001I0 1O 13 someone should help me with this question Whats the area of a triangle with sides of 24, 38 and 14 Awnser please jsjshshshdh Which type of chlorophyll is rare in xanthophyceae and is only determine its two genera What is Commercial Advertising? What advice does Odysseus have for Amphinomus Rachel finished 3/4of the race in 6 hours. How long was the entire race? why did Baptist Minister Garrison frazier believe that land was what African-Americans wanted most after the war 2.How does Ulysses exhibit good leadership skills in this passage? What traits do you thinkare necessary for a leader to possess? Cite evidence from this text, your own experience,and other literature, art, or history in your answer. A 3 column table with 5 rows. Column 1 is labeled State with entries Florida, Michigan, New York, California, Texas. Column 2 is labeled Republican primary (percentage) with entries 12. 8, 16. 5, 1. 4, 22. 9, 12. 8. Column 3 is labeled General Election (percentage) with entries 63. 5, 64. 7, 53. 1, 55. 2, 49. 7. Look at the table. What conclusion do the data in the table support? Voters are more likely to participate in a presidential election than in a primary. Texas and Florida have the same number of Republican voters. Voters are more likely to participate in a primary than in a presidential election. California has more Republicans than New York. Circle A was dilated with the origin as the center of dilation to creat circle b Base your answer(s) to the following question on the diagrams below and your knowledge of biology. The diagrams represent two different cells and some of their parts. The diagrams are not drawn to scale. Which statement best describes these cells? / why we use this symbol I AM ON MY LAST BRAINLY POINTS! NOBODY WILL HELP ME T-T! EVERYBODY SENDS ME RANDOM LINKS! IF U HELP ME U CAN GET THE CROWNDavid mixed 5 3/8 cups of popcorn with 3 5/8 cups of pretzels. He then divided the snack into bags with 2/3 cups in each. After dividing, how many bags of snack bags will David have? Can someone plz help me? :,) don't/I/quite/know/what/to/I/ought/do ASAP HELP 100 points!! Which answer describes this poem? A secondary source recounting oral histories A primary source recording events as they happen A primary source documenting of one of the participants A secondary resource describing an event in the past Gasoline has a density of 0.7197 grams per milliliter. Calculate the mass, in grams, of a sample of gasoline with a volume of 48.5 milliliters. Graph the functionf(x) = 3/5x - 5