Cell are small and us human can't see them with our own eyes. it is in possible to see cell without a microscope
........................z......
Answer:
The Greenhouse Effect Revisited. When solar energy strikes the planet during the day, the ground, highways and other objects get hot and absorb that energy. As the sun goes down, the Earth cools by giving off infrared radiation. Because greenhouse gases absorb part of this radiation, the atmosphere warms and keeps the Earth from getting too cold.
When you touch<span> a doorknob (or something else made of metal), which has a positive charge with few electrons.</span>
W = _|....F*dx*cos(a)........With F=force, x=distance over which force acts on object,
.......0.............................and a=angle between force and direction of travel.
Since the force is constant in this case we don't need the equation to be an integral expression, and since the force in question - the force of friction - is always precisely opposite the direction of travel (which makes (a) equal to 180 deg, and cos(a) equal to -1) the equation can be rewritted like so:
W = F*x*(-1) ............ or ............. W = -F*x
The force of friction is given by the equation: Ffriction = Fnormal*(coeff of friction)
Also, note that the total work is the sum of all 45 passes by the sandpaper. So our final equation, when Ffriction is substituted, is:
W = (-45)(Fnormal)(coeff of friction)(distance)
W = (-45)...(1.8N).........(0.92).........(0.15m)
W = ................-11.178 Joules
