Two metal plates 4 cm long are held horizontally 3 cm apart in a vacuum, one being vertically above other. The upper plate is at a potential of 3000 & the lower is earthed. Electrons having a velocity of 1×10^7 m/s are injected horizontally midway between the plates & in the direction parallel to 4 cm edge. Calculate the vertical deflection of the electron beams as it emerges from the plates. (Assume “e/m=1.8×10^11 c/kg”).

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?