The wave-particle dual nature of light has been documented and tested many times.
Choice A
We have no idea. We need to examine the experimental set-up. You've given us no information, except that there may have been some sort of collision.
Answer:
a) 35.94 ms⁻²
b) 65.85 m
Explanation:
Take down the data:
ρ = 1000kg/m3
a) First, we need to establish the total pressure of the water in the tank. Note the that the tanks is closed. It means that the total pressure, Ptot, at the bottom of the tank is the sum of the pressure of the water plus the air trapped between the tank rook and water. In other words:
Ptot = Pgas + Pwater
However, the air is the one influencing the water to move, so elimininating Pwater the equation becomes:
Ptot = Pgas
= 6.46 × 10⁵ Pa
The change in pressure is given by the continuity equation:
ΔP = 1/2ρv²
where v is the velocity of the water as it exits the tank.
Calculating:
6.46 × 10⁵ =1/2 ×1000×v²
solving for v, we get v = 35.94 ms⁻²
b) The Bernoulli's equation will be applicable here.
The water is coming out with the same pressure, therefore, the equation will be:
ΔP = ρgh
6.46 × 10⁵ = 1000 x 9.81 x h
h = 65.85 meters
Answer:
the final velocity of the wagon is 6 m/s.
Explanation:
Given;
initial velocity of the wagon, u = 4 m/s
mass of the wagon, m = 35 kg
energy applied to the wagon, E = 350 J
The final velocity of the wagon is calculated as;
E = ¹/₂m(v² - u²)

Therefore, the final velocity of the wagon is 6 m/s.
The green is ground. Ideally, no current travels in this one. The red and black are the power and neutral wires but which colors they are depends on a convention. In the US, you will actually have a black (power) and a white (neutral) Here it's red and black and usually in a red/black system the red is the power. Either way there is a potential of 120V rms between them.