Question

What happens when gasoline is used to power a vehicle?

A.
Energy is gained as chemical energy transforms to heat energy but lost as heat energy transforms to mechanical.

B.
Energy is lost as chemical energy transforms to heat energy but gained as heat energy transforms to mechanical.

C.
Energy is neither lost nor gained as it transforms from chemical, to potential, to electrical energy.

D.
Energy is neither lost nor gained as it transforms from chemical, to heat, to mechanical energy

Answer 1

@TrojanPoem @maymuna

Answer 2

a or d

Answer 3

d

energy is never lost and is never gained from nothing

Answer 4

k

Answer 5

According to the law of conservation of energy, when a motorcycle uses 5500 J of chemical energy from gasoline, how much of this energy will be transformed into mechanical, sound, or heat energy?

A.
1375 J

B.
2750 J

C.
11,000 J

D.
5500 J

Answer 6

d

Answer 7

Good.

Answer 8

k

Answer 9

Isn't this physics ?

Answer 10

i put it in wrong one

Answer 11

:)

Answer 12

i will go to physics

Answer 13

ok

Answer 14

It doesn't matter, I was just curious to know.

Answer 15

ok

Answer 16

Which scientific term is defined as the rate at which work is accomplished?

A.
potential

B.
energy

C.
mechanics

D.
power

Answer 17

d

Answer 18

@TrojanPoem

Answer 19

rate of work = w/t = power

Answer 20

Any rate is division over t , any specific is over mass (m)

Answer 21

what do you mean

Answer 22

so was i right

Answer 23

You were.

Answer 24

ok

Answer 25

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

A.
300 N

B.
300 J

C.
30,000 N

D.
30,000 J

Answer 26

d

Answer 27

S = 100 m
F = 300 N

W = FS
= 100 * 300 = 3x 10^4 J (D)

You're correct.

Answer 28

c

Answer 29

-,- C is wrong you were right when you said D

Answer 30

ok

Answer 31

According to the scientific definition, which is not an example of work?

A.
pushing a tack into a block of cork

B.
pulling a nail out of a piece of wood

C.
brushing teeth

D.
leaning against a large cargo crate

Answer 32

d maybe

Answer 33

W = FD
1) push ( we have force, distance) -> there is work
2) we have force and distance _> there is work
c) we are moving the brush there is froce , distance
d) we are leaning ( not distance s/d = 0)
W = f * 0 = 0 j

the correct answer is d

Answer 34

The scientific definition of work is the transfer of energy from one object to another, especially in order to make the second object move in a certain direction

Answer 35

ok

Answer 36

Which describes how a simple machine can make work easier?

A.
It magnifies the kinetic energy so that the potential energy is greater.

B.
It magnifies the potential energy so that the kinetic energy is greater.

C.
It magnifies the output force so that the input force is greater.

D.
It magnifies the input force so that force is greater.

Answer 37

a

Answer 38

@TrojanPoem

Answer 39

@TrojanPoem

Answer 40

I think D, but not sure.

I remember taking the formula but can't recall it :/ don't count on me.

Answer 41

ok

Answer 42

What principal of a lever is being used in this photograph?



A.
A bottle opener is a type of lever that magnifies the output force required.

B.
A bottle opener is a type of lever that reduces the input force required by reducing the distance over which the force is applied.

C.
A bottle opener is a lever in which a smaller input force acts over a larger distance so that a larger output force can act over a smaller distance.

D.
A bottle opener is a type of lever that enables the same work to be done over a shorter distance with less force.

Answer 43

https://static.k12.com/calms_media/media/1473000_1473500/1473258/2/3a30ef557b66c434cfd71485b66f17225db08229/SHU_58802875_bottle_can_opener_E.jpg

Answer 44

c

Answer 45

@TrojanPoem

Answer 46

Which describes the relationship between potential and kinetic energy of a ball thrown up in the air as it falls back to the ground?

A.
Kinetic energy equals gravitational potential energy.

B.
Gravitational potential energy increases; kinetic energy increases.

C.
Kinetic energy increases; gravitational potential energy decreases.

D.
The mass of the ball is required to answer this.

Answer 47

A bottle opener is a lever in which a smaller input force acts over a larger distance so that a larger output force can act over a smaller distance.

Answer 48

Sorry , I was checking another question

Answer 49

Guess the answer

Answer 50

c

Answer 51

K.E = 0.5 mv^2 , P.E = mhg

K.E + P.E = const

so when P.E increase, K,E decrease and vice versa

C.
Kinetic energy increases; gravitational potential energy decreases.

Answer 52

Two iron blocks are the same size. One block has a higher temperature than the other. Which describes the thermal energy of these blocks?

A.
Lower temperature means greater kinetic energy, which means the colder block has greater thermal energy.

B.
Higher temperature means greater potential energy, which means the warmer block has greater thermal energy.

C.
Lower temperature means greater potential energy, which means the colder block has greater thermal energy.

D.
Higher temperature means greater kinetic energy, which means the warmer block has greater thermal energy.

Answer 53

d

Answer 54

right.

Answer 55

Which describes the behavior of heat?

A.
the transfer of thermal energy from objects with higher potential energy to objects with lower potential energy

B.
the transfer of thermal energy from hotter objects to colder objects

C.
the transfer of thermal energy from colder objects to hotter objects

D.
the transfer of thermal energy from objects with lower kinetic energy to objects with higher kinetic energy

Answer 56

b

Answer 57

right.

Answer 58

How does using a ramp to load boxes into a truck make work easier?

A.
Using the ramp increases the amount of force needed to move the boxes, but the boxes must be moved over a shorter distance.

B.
Using the ramp decreases the amount of force needed to move the boxes, but the boxes must be moved over a longer distance.

C.
Using the ramp decreases the amount of force needed to move the boxes, but the boxes must be moved over a shorter distance.

D.
Using the ramp increases the amount of force needed to move the boxes, but the boxes must be moved over a longer distance.
Question Resources

Answer 59

c

Answer 60

right

Answer 61

Give me a moment.

Answer 62

ok

Answer 63

i will put the ? and guess than you check them

Answer 64

Which describes the difference between a bowling ball sitting in the rack waiting to be used and the bowling ball knocking pins down?

A.
In the rack and when knocking down pins, the potential energy and the kinetic energy of the bowling ball are equal.

B.
In the rack, the bowling ball has only kinetic energy. As it knocks pins down, its potential energy has increased, while its kinetic energy has decreased.

C.
In the rack, the bowling ball has no energy at all. As it knocks down the pins the energy is 75% kinetic and 25% potential.

D.
In the rack, the bowling ball has only potential energy. As it knocks pins down, its potential energy has decreased, while its kinetic energy has increased.

Answer 65

d

Answer 66

@maymuna

Answer 67

Which is an accurate description of the thermal energy of an entire house when compared with the thermal energy of a small bedroom in that house at the same temperature?

A.
The total potential energy of the particles in a substance is its thermal energy. The entire house is larger than the small bedroom, so it contains more particles. Therefore, the entire house has the greater thermal energy.

B.
The total kinetic energy and potential energy of the particles in a substance is its thermal energy. The entire house is larger than the small bedroom, so it contains more particles. Therefore, the entire house has the greater thermal energy.

C.
The total potential energy of the particles in a substance is its thermal energy. The particles in the entire house are more spread out, so it contains fewer particles than the bedroom. Therefore, it is the bedroom that has the greater thermal energy.

D.
The total kinetic energy of the particles in a substance is its thermal energy. The particles in the entire house are more spread out, so it contains fewer particles than the bedroom. Therefore, it is the bedroom that has the greater thermal energy.

Answer 68

d

Answer 69

Which states the law of conservation of energy?

A.
Energy can be created or destroyed, but it can not be converted or changed into different forms.

B.
Energy can be created or destroyed, and it can be converted or changed into different forms.

C.
Energy cannot be created or destroyed, but it can be converted or changed into different forms.

D.
Energy cannot be created or destroyed, nor can it be converted or changed into different forms.

Answer 70

c

Answer 71

Use this formula to solve this problem:

Power (P) = Work (W) ÷ time (t)

Sara's body supplies a force of 300 N to run up a 15 meter hill in 10 seconds.

How much power is involved in Sara's run up the hill?

A.
2 Watts

B.
20 Watts

C.
30 Watts

D.
450 Watts

Answer 72

d

Answer 73

The answer is A.

Answer 74

hi

Answer 75

is it

Answer 76

medal

Answer 77

prove it

Answer 78

@TrojanPoem can you check them

Answer 79

Thermal energy need not be the same. Consider the thermal energy in a cup of water and a bathtub of water, at the same temperature. There is much more energy in the water in the tub, because there is much more water. The temperature shows the thermal intensity, which is the same here

Answer 80

can you tell me the ones i got them wrong

Answer 81

@trwatkins1

Answer 82

@TrojanPoem

Answer 83

thanks

Answer 84

i passed