Which answer shows a balanced nuclear equation for the alpha decay of plutonium-239

Answer: An alpha particle is a helium-4 nucleus, it contains gwo protons and two neutrons. So, alpha decay, giving off an alpha particle, does the following:

1)reduces the atomic number (number of just protons) by two. Plutonium has atomic number of 94, take two protons away and you are left with 92 which corresponds to uranium.

2) reduces the mass number (protons plus neutrons) by 4. If you start with 239 and subtract two protons and two neutrons, you are left with 235.

Explanation:

Using the formula for work, Match the Force × Distance problems with their correct "Work Performed" answer. The first example has been completed for you.

Force × Distance = Work Performed

10 newtons 6 meters =60 Nm

1. 62 Nm
40 pounds 100 feet

2. 4000ft.-lbs.
2.5 pounds 24 inches

3. 5 ft.-lbs
62 newtons 1 meter

4. 200ft.-lbs.
1 ton 20 feet

5. 40,000 ft.-lbs.
400 pounds 0.5 feet

Two identical negative charges exert a repellent force of 150 N on each other when they are 40 cm apart. that is the magnitude of each negative charge?
a. 2.7 nC
b. 51.6 microC
c. 0.67 microC
d. 0.82 mC

What is the flaw with using apparent brightness rather than absolute brightness to determine the brightness of a star?

Apparent brightness does not use the star's color or temperature.

Apparent brightness does not take into account the distance of the star from Earth

Apparent brightness is only theoretical, its value cannot be directly measured with equipment

Apparent brightness is only on a comparative scale that determines how bright a star looks from a theoretical distance of 10 parsecs
from Earth.

Don’t answer if you’re just going to put a link or file.

Help if you know and are sure

Energy that comes from the sun—solar energy—is clean. It does not cause pollution the way energy from fossil fuels (like gas and oil) does. However, solar energy must be collected before it can be used. The instruments used to collect solar energy are quite costly.

This paragraph states that solar energy ________.

A) causes a lot of pollution
B) is expensive to collect
C) is one kind of fossil fuel
D) is a cheap way to get energy

Describe a situation where you have (or could) encountered Newton's 3rd law. What are the consequences of unbalanced forces? will give brainliest to the first answer!

For the effective radiation of heat from an electric heater. Why should we polish it to shine but not keep it clean or paint it green or black?

PLEASE HELP SOLVE THIS PHOTO BELOW

Witch statement best describes a line graph? open image to see

What do radio waves and microwaves have in common?

Both are at the side of the spectrum that has the highest frequency.

Both have shorter wavelengths than visible light.

Both have lower frequencies than visible light.

Both have radiant energy than visible light.

Why does a nucleus always have a positive charge?

look at screenshot and please answer as quick as possible

What does it mean that energy cannot be created or destroyed?
A. Potential energy cannot be transformed into kinetic energy
B. Energy can only be transformed
C. Kinetic energy cannot be transformed into kinetic energy
D. Kinetic energy cannot be transformed into potential energy

Justin and Oscar each hit a baseball with a bat. The baseballs have the same mass, but the ball Justin hits has a greater acceleration. What might be the reason for the greater acceleration of Justin's baseball?

Which is the definition of the equator?
A. The equator is half of a sphere, which is used to describe one half of the Earth.
B. The equator is the imaginary line that divides the Earth into two equal parts. It is also used as the basis for the word’s time zones.
The equator is the imaginary line that divides the Earth into two equal parts. It is also used as the basis for the word’s time zones.

C. The equator is an imaginary horizontal line drawn on the Earth equally between the North and South poles.


D. The equator is half of a circle used to describe the northern half of the Earth.

Which effect is created when two sound waves that are close in pitch
interact?
O A. Echoes
O B. Loudness
C. Beats
O D. Intensity

Create your own real world example of how the application of they scientific discovery has help create a new technology

Lab Report
Motion and Forces
It’s time to complete your Lab Report. Save the lab to your computer with the correct unit number, lab name, and your name at the end of the file name (e.g., U4_ Lab_MotionAndForces_Alice_Jones.doc).
Introduction
What was the purpose purpose of the experiment?
The purpose of the experiment is to test the hypothesis.
What were the independent, dependent, and control variables in your investigation? Describe the variables for each part of the experiment.


Write a hypothesis based on observations and scientific principles.
Type your answer here:
Experimental Methods
What tools did you use to collect your data?
Questionnaires and observations.
Write your procedure. List each step so that another student could follow the procedure and repeat your experiment.
Type your answer here:
Data and Observations
Record your observations.
Type your answer here:
Conclusions
What conclusions can you draw about how the sum of forces acting on an object affect its motion? Write an evidence-based claim.
Type your answer here:
Which mass, A, B, or C, was the greatest? Use the observations from your experiment and your knowledge of Newton’s laws of motion to write an evidence-based claim.
Type your answer here:
Make a model that shows the forces acting on two blocks on a flat, frictionless surface:
A 1 N block at rest
A 1 N block with 2 N of force applied in one horizontal direction
Include arrows to represent the forces and labels to indicate the magnitude of each force. Use your model to compare and explain the motion of each block.
Type your answer here:

A piece of glass floats in a liquid with a density of 2.6 g/mL. Which type(s) of glass could it be?

How can you drop two eggs the fewest amount of times, without them breaking? ...

How do instantaneous speed and average speed differ? please help me guys or i will death lol

Can someone help me with this I'm-- never mind I would just like help..

Can someone please help me on thisss

Forced is measured by...
Group of answer choices

A. Power

B. Newtons

C. All of the above

D. Kelleys

Help, please............................................................

What two gases in the atmosphere do animals and plants need to breathe and grow?

How much is the mass of aluminum with a volume of 1 m3 less than the mass of lead of the same volume?

Plz helppppppppp meeeeeeeeeeeeeeee
What does the liquid or melted crayon represent in this model?

Edward deposited ​$10,000 into a savings account 5 years ago. The simple interest rate is ​3%. How much money did earn in​ interest?

PLEASE HELP
Highlight the objects or materials items that are made of cells and did originate from cells.

Please Help I Still Have More Assignments To Deal With And Any Help Would Be Appreciated Along With An Explanation