Charging phenomenon is basically transfer of electrons from one system to other. When a system loses the electrons the it becomes positively charged and when a system gains electrons then it will become negatively charged
so here if slab is rub against fur then one of them will lose the electrons while other will gain the electrons and hence one will get negatively charged and other will get positive charge
Here it is given that slab get negatively charged so correct options are
<em>3. Electrons move from the fur to the slab.
</em>
<em>6. The fur becomes positive after rubbing the slab.
</em>
Answer:
The magnitude of force must you apply to hold the platform in this position = 888.89 N
Explanation:
Given that :
Workdone (W) = 80.0 J
length x = 0.180 m
The equation for this work done by the spring is expressed as:
Making the spring constant 
the subject of the formula; we have:
Substituting our given values, we have:
The magnitude of the force that must be apply to the hold platform in this position is given by the formula :
F = 888.89 N
<span>If there isn't any force then the normal contact force will be
N=m*g=7.5*9.81=73.58N
which is 73.58-23=50.58N less
so, there the person must pull at 23 degree upward
break down the tension in two components, vertical and horizontal.
vertical tension= 50.58=T*sin23
T=50.58/sin23=129.45N</span>
