Question

May someone check my work for science

Answer 1

@sleepyjess

Answer 2

sure go ahead

Answer 3

ok thank you

Answer 4

Which of the following choices defines energy in scientific terms?

A. the motion of an object
B. the ability to do work
C. a force multiplied by distance
D. a change in temperature
My answer is B.

Answer 5

@Fransisco_w

Answer 6

is it correct\\

Answer 7

Yep that is correct!

Answer 8

can you check some more

Answer 9

Is that it?

Answer 10

What happens when a lamp plugged into an electrical outlet is turned on?

Energy is lost.
Energy is gained.
The form of energy changes, but the total energy remains the same.
The form of energy changes and the total energy increases.

Answer 11

I think also D. because the internal energy of a perfect gas, is proportional to the absolute temperature of that gas

Answer 12

My answer is C.

Answer 13

is it correct

Answer 14

@kiarakaykay ok!

Answer 15

what does that mean

Answer 16

@kiarakaykay It means that I agree with you!

Answer 17

ok can you check more

Answer 18

I would say its C. because the energy is changing and you cannot get more energy by converting it so it can't be D.

Answer 19

According to the law of conservation of energy, when a car uses 10,000 J of chemical energy from gasoline, how much of this energy will be transformed into mechanical, sound, or heat energy?

2500 J
5000 J
10,000 J
20,000 J

Answer 20

My answer is 10,000 J

Answer 21

@Fransisco_w please note that I said the the content of energy of a perfect gas is proportional to the absolute temperature.

Answer 22

Is that correct @Fransisco_w and @Michele_Laino

Answer 23

Yes it would be C. 10,000

Answer 24

@kiarakaykay I think the first option, because the engine of a car, as termal machine has a low efficiency, namely about 40%

Answer 25

In scientific terms, how is power related to work?

Power is the force of work over a certain distance.
Power is the ability to do work.
Power is the energy supplied in a force.
Power is the rate at which work is accomplished.

Answer 26

My answer is Power is the rate at which work is accomplished.

Answer 27

@Michele_Laino It is not only asking about mechanical it is asking about all three. A car only produces those 3 energies, so it would use it all

Answer 28

I think, using the definition of power, is the last option

Answer 29

How much work is accomplished when a force of 300 N pushes a box across the floor for a distance of 100 meters?

300 N
30,000 N
300 J
30,000 J

Answer 30

@Fransisco_w Sorry, you are right!

Answer 31

My answer is 30,000 j

Answer 32

@kiarakaykay that's right!

Answer 33

Which of the following is not an example of work, according to the scientific definition?

lifting a suitcase off the floor

leaning against a brick wall on the side of a building
pulling a sled across the snow
pushing a grocery cart

Answer 34

Slow down the questions

Answer 35

My answer is leaning against a brick wall on the side of a building

Answer 36

ok

Answer 37

@kiarakaykay that's right there is no motion

Answer 38

You are correct!

Answer 39

How do simple machines make work easier?

They change the strength or direction of a force.
They apply force quickly.
They decrease the power available.
They maintain the distance of a force.

Answer 40

Now that one was a little difficult

Answer 41

It would be A. because a simple machine like a wheel barrow changes the amount of strength needed to move materials.

Answer 42

I think the first option, for example think to inclined plane. By inclined plane you get a reduction of the strength of a force that you have to apply in order to lift a weigth

Answer 43

What has changed when a gardener uses a lever to lift a rock, instead of lifting it by hand?

More force is applied over a longer distance.
Less force is applied over a longer distance.
More force is applied over a shorter distance.
Less force is applied over a shorter distance.

Answer 44

That one is hard too

Answer 45

Lever? I do not know what it is meaning? Like lever you pull to open something or some kind of gardening tool?

Answer 46

ok

Answer 47

well instead can you help me with another i figured out the answer

Answer 48

Hey, I have to get to class so I can't any more D:

Answer 49

can't help*

Answer 50

ok

Answer 51

@Michele_Laino

Answer 52

I think the second option, namely less force over longer distance, because a lever reduce the force applied on it, evenif the work done has to be equal in both cases, namely with or without a lever

Answer 53

Which scientific description of heat is accurate?

Heat is the total thermal energy of any single object.
Heat is the average kinetic energy of atoms in an object.
Heat is the flow of thermal energy from one object to another.
Heat is the total kinetic energy of atoms in an object.

Answer 54

@kiarakaykay

Answer 55

can you help me

Answer 56

@sleepyjess

Answer 57

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