Question1
An inkjet printer, letters are built up by squirting drops of ink at a paper from a rapidly moving nozzle. The pattern on the paper is controlled by an electrostatic valve that determines at each nozzle position whether ink is squirted onto the paper or not. The ink drops have a radius of 19.0 and leave the nozzle and travel toward the paper at a velocity of 25.0. The drops pass throughout the charging unit that gives each drop a positive charge q by causing it to lose some electrons. The drops then pass between parallel deflecting plates of length 1.60 where there is a uniform vertical electric field with a magnitude of 8.05×104.
If a drop is to be deflected a distance of 0.350 by the time it reaches the end of the deflection plate, what magnitude of charge must be given to the drop? (Suppose that the density of the ink drop is).
Question2
A 8.0g bullet is fired into a 12kg wood block that is at rest on a wood table. The block, with bullet embedded, slides 5.0cm across the table. The coefficient of kinetic friction for wood sliding on wood is 0.20. What is the final speed of the bullet?