Answer:
Explanation:
The voltage of a disconnected charged capacitor increases when the plate area is decreased.
When plate area decreases , capacitance C decreases , but charge Q remains constant .
Q = C V where C is capacitance and V is voltage .
when C decreases , V increases for keeping Q constant .
So the statement is true.
The electric field is dependent on the charge density on the plates.
This statement is true .
The voltage of a connected charged capacitor remains the same when the plate area is decreased .
For a connected capacitor , V or voltage is constant which is equal to voltage of charging battery .
So the statement is true .
Speed uses distance and velocity uses displacement in its calculation.
For 100 m race, distance = displacement. Hence speed = velocity
For 400m race, distance ≠ displacement. distance = 400m whereas displacement = 0m. Hence speed ≠ velocity
The relationship between frequency and wavelength for an electromagnetic wave is

where
f is the frequency

is the wavelength

is the speed of light.
For the light in our problem, the frequency is

, so its wavelength is (re-arranging the previous formula)
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.
It would be 78 becuase the 2 percent of 64 is many of energy lost