Answer:
dart
Explanation:
dart and sun and water so that the plant be okay
<u>Answer </u>
A. that the initial gravitational potential energy of the masses transformed into kinetic energy of the paddles and then to thermal energy in the water
<u>Explanation</u>
James Joule allowed some water to fall from a height of 1 foot. the water would turn a paddle wheel at the bottom causing a temperature of water to raise.
The height form which the water fell, mass and the temperature of water was measured and used to calculate mechanical equivalent of heat.
From the choices given the best answer is A. that the initial gravitational potential energy of the masses transformed into kinetic energy of the paddles and then to thermal energy in the water.
Answer:

Upward
Explanation:
We are given that
Mass of scarp paper,
1mg=
Distance,d =8 mm=
Magnitude of electric force =
Where 
Substitute the values


Gravitational force act in downward direction.
The electric force acts in opposite direction and magnitude of electric force is equal to gravitational force.
Hence, the direction of electric force is upward.
Answer: 39.8 μC
Explanation:
The magnitude of the electric field generated by a capacitor is given by:

d is the distance between the plates.
For a capacitor, charge Q = CV where C is the capacitance and V is the voltage.

where A is the area of the plate and ε₀ is the absolute permittivity.
substituting, we get

It is given that the magnitude of the electric field that can exist in the capacitor before air breaks down is, E = 3 × 10⁶ N/C.
radius of the plates of the capacitor, r = 69 cm = 0.69 m
Area of the plates, A = πr² = 1.5 m²
Thus, the maximum charge that can be placed on disks without a spark is:
Q = E×ε₀×A
⇒ Q = 3 × 10⁶ N/C × 8.85 × 10⁻¹² F/m × 1.5 m² = 39.8 × 10⁻⁶ C = 39.8 μC.