Explanation:
Coal is a fossil fuel and is the altered remains of prehistoric vegetation. The energy we get from coal today comes from the energy that plants absorbed from the sun millions of years ago. In the burning process of coal, carbon dioxide (CO2) is emitted. Humans expel CO2, and plants utilize it every single day. Carbon is a building block for all forms of life and is used in a lot of everyday products.
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. However, many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras.
Answer:
Because there is no net force acting o an object in equilibrium.
Explanation:
When object is in equilibrium (either at rest or moving with constant velocity, the net force acting o it is zero.A vector can only have zero magnitude fall of its components are zero this means that all forces acting on the object are balanced.
Answer:
q = 0.384 C
Explanation:
The total charge present at the head can be easily found out by multiplying the charge on a single electron with the total number of electrons present on the head:

where,
q = total charge on head = ?
n = total no. of electrons on the head = 2.4 x 10¹⁸
e = charge on 1 electron = 1.6 x 10⁻¹⁹ C
Therefore,

<u>q = 0.384 C</u>
Answer:
0.2289
Explanation:
Power required to climb= Fv where F is force and v is soeed. We know that F= mg hence Power, P= mgv and substituting 700 kg for m, 9.81 for g and 2.5 m/s for v then
P= 700*9.81*2.5=17167.5 W= 17.1675 kW
To express it as a fraction of 75 kw then 17.1675/75=0.2289 or 22.89%
Plot a graph, constant speed of movements represented as straight lines. Time on X axis (seconds) and position on Y axis (metres) , calculated by moving, e.g 4metres in a second.