mass of the bottle in each case is M = 0.250 kg
now as per given speeds we can use the formula of kinetic energy to find it
1) when speed is 2 m/s
kinetic energy is given as


2) when speed is 3 m/s
kinetic energy is given as


3) when speed is 4 m/s
kinetic energy is given as


4) when speed is 5 m/s
kinetic energy is given as


5) when speed is 6 m/s
kinetic energy is given as


Answer: solenoid
Explanation: solenoid: increase strength around electromagnetic fields
The initial velocity (its speed before falling off) is approximately 1.95 m/s