Answer: Next time you create a question, add an image or PDF. Because I do not know the question. So, may you please create a new question?
Volume = mass/density
Volume = 15000 g/45 g/cm3 ≈ 333.3 cm<span>3</span>
Answer:
The sound intensity of train is 1000 times greater than that of the library.
Explanation:
We have expression for sound intensity level,

A train whistle has a sound intensity level of 70 dB
We have

A library has a sound intensity level of about 40 dB
We also have

Dividing both equations

The sound intensity of train is 1000 times greater than that of the library.
First let us calculate for the angle of inclination using
the sin function,
sin θ = 1 m / 4 m
θ = 14.48°
Then we calculate the work done by the movers using the
formula:
W = Fnet * d
So we must calculate for the value of Fnet first. Fnet is
force due to weight minus the frictional force.
Fnet = m g sinθ – μ m g cosθ
Fnet = 1,500 sin14.48 – 0.2 * 1,500 * cos14.48
Fnet = 84.526 N
So the work exerted is equal to:
W = 84.526 N * 4 m
<span>W = 338.10 J</span>
Answer:
Explanation:
The source of all forms of energy found on the earth except nuclear energy is the sun . So energy used by us to do daily activities also comes from the sun .
The plants trap the solar energy in the form of light to make food material for us like sugar , carbohydrates etc . This energy is stored here in the chemical bonds formed in them.
We take this food in the form of carbohydrate, fat etc. We digest it to mix this food carbohydrate in blood . It is further broken down on being absorbed by the cell in our body . They break them to produce a compound like ATP ( adenocine triphosphate ) which is energy rich compound . It is converted into ADP and difference of energy is released . This energy is used by us in moving body parts.