Answer:
I'd say C is the answer they want, though my pedantic side wants to argue for B being true as well.
Answer:
The law of conservation of mass or principle of mass conservation
Explanation:
It states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so quantity can neither be added nor be removed.
Energy stored in a capacitor is Electric Potential Energy. Capacitor is device used for storing energy. The work done to charge is a capacitor is stored in it in the form of Electrical potential energy. Electrical potential energy is defined as capacity to do work due to the position change. For example, we know fans have capacitor installed in it. When we turn off the fan, it continue moving using the electrical energy stored in the capacitor.
Answer:
v = 79.2 m/s
Solution:
As per the question:
Mass of the object, m = 250 g = 0.250 kg
Angle, 
Coefficient of kinetic friction, 
Mass attached to the string, m = 0.200 kg
Distance, d = 30 cm = 0.03 m
Now,
The tension in the string is given by:
(1)
Also
T = m(g + a)
Thus eqn (1) can be written as:





Now, the speed is given by the third eqn of motion with initial velocity being zero:

where
u = initial velocity = 0
Thus

