To solve this problem we will consider the definition of Minimum Energy, as the change between the minimum voltage and its distance. Mathematically it can be written as

Rearranging to find the Voltage,

Replacing,


Therefore the minimum voltage needed between your finger and the doorknob to generate this spark is 28.5kV
high velocity is the answer as baby oil is dense
Answer:
Nodes = 5 and antinodes = 4
Explanation:
Nodes are the points of zero amplitude and appear to be fixed. On the other hand, antinodes are points on a stationary wave that oscillates with maximum amplitude.
In this given standing wave, there are 5 points where the amplitude is 0. So, there are 5 nodes. Also, there are 4 points where the amplitude is maximum.
So, there are 5 nodes and 4 antinodes.
The equation for kinetic energy is,
Ke = (1/2)mv^2.
You're given a kinetic energy of 790 joules, and a speed of 1.6 m/s. Plugging these values into the equation, we get,
790 = (1/2)(1.6)^2(m).
Solving for m, we get,
m = (790)/(0.5(1.6)^2).
I'll let you crunch out those numbers for yourself :D
If you have any questions, feel free to ask. Hope this helps!
Answer:
5m
Explanation:

Use the Pythagorean theorem to calculate the long edge of the triangle, which would be his displacement.