Ans: 4 ..
A bullet of mass 25 g strikes horizontally a block of wood with a velocity of 250 m s' and
penetrates it a distance of 1.0 m. Calculate the resistance of the wood on the bullet, assuming the
resistance to be uniform. How far would the bullet have penetrated, if the speed of the bullet had
been 200 m s-1?
Ans: – 781.25 N, 0.64 m
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It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (for example, would the velocity of a neutral particle be selected by passage through this device? ) the explanation of this is that the mass and the charge control the resolution of the device--particles with the wrong velocity will be accelerated away from the straight line and will not pass through the exit slit. if the acceleration depends strongly on the velocity, then particles with just slightly wrong velocities will feel a substantial transverse acceleration and will not exit the selector. because the acc