Answer:
a)
, b) 
Explanation:
The magnitude of torque is a form of moment, that is, a product of force and lever arm (distance), and force is the product of mass and acceleration for rotating systems with constant mass. That is:



Where
is the angular acceleration, which is constant as torque is constant. Angular deceleration experimented by the unpowered flywheel is:


Now, angular velocities of the unpowered flywheel at 50 seconds and 100 seconds are, respectively:
a) t = 50 s.


b) t = 100 s.
Given that friction is of reactive nature. Frictional torque works on the unpowered flywheel until angular velocity is reduced to zero, whose instant is:


Since
, then the angular velocity is equal to zero. Therefore:

You’ll need 4H20 molecules to balance the equation.
Answer:
Option C
Explanation:
The graph shows endothermic reaction because the reactants are lower in energy and the products are higher is energy. Endothermic reactions absorb energy having products with higher energy.
These balloons will be attracted, as you have shown in the picture, there are two positives, they are not in the same spot. when two of the same poles are put together, they rebel each other, since the two positive poles are not in the same area of the balloon, the balloons will attract each other. I hope this helps :)
I think the correct answer would be to electrolyze water (run an electric current through it) to decompose it into hydrogen and oxygen. Assuming 100% efficiency, it is said that it needs about 40kWh per kilogram of water to fully decompose it.