The Banana Challenge is a hilarious idea, some of the responses seem to miss the point. The effect of gravity is indeed supposed to move all objects, proportional to mass and distance. I'll start with a thought experiment. According to the FDA, the average banana weighs 120 grams. So, let us place two 120 gram bananas a centimeter apart and calculate the gravitational force. I could calculate it myself, or I could use

https://www.omnicalculator.com/physics/gravitational-force. Using the calculator, we can find that two bananas with center of mass 1 cm apart have a gravitational force of 9.611 × 10^-9 N, or a 9th of the force that a hydrogen nucleus exerts on it's electron. Oh dear. So bananas really don't attract each other very much. However, you asked me to demonstrate gravity, so I'll persevere.

*Assume a 1000 kg banana*. When two of these are positioned with the centers one cm apart, the force of gravity is 0.66743 N, or around the force it takes to depress a key on a keyboard. So then, sir, you ask me to demonstrate gravity with bananas?

*Give me a couple of one ton bananas, then we can talk.*Anyways, the whole point of this thread is for Flat Earthers and Round Earthers to come to a consensus on a workable Cavendish Experiment, so I'll modify the writeup.

1. Suspend a wire (exact length, gauge, and material TBD) from the ceiling (Could be performed in a large empty space, such as an empty gymnasium to minimize outside gravitational influences, or could be performed in a vacuum chamber if it's practical.

2. On the end of the wire, attach a beam (properties TBD) and to either side attach a weight of mass (TBD). Allow the system to rest for one hour.

3.

~~Place a digital dial gauge under the beam so that it is measuring the height of the beam, and rotate the beam 90 degrees without allowing the wire to swing. Release and plot the height over the next (length of time TBD).~~ Attach a mirror to the beam, and using a laser, establish the angle of deflection. Allow the system to come to equilibrium, and record the angle.

4. Place two empty containers of volume (TBD) (TBD m/cm) away, on scales of which the mass is already known. Wait one hour and measure the change in

~~height~~ angle of the beam.

5. Fill the containers with (material of extremely high density: lead, stone, etc.), so that the mass of each container is (TBD). Wait until the system reaches equilibrium and measure the

~~height~~ angle.

6. Remove the containers and allow the system to return to equilibrium.

Looking forward to further collaboration!