7 A stationary gun of mass 4.8kg mounted on wheels is in a battlefield At fires a bullet of mass 85g to the right with a velocity of vms The bullet moves horizontally and hits a stationary
wooden block of mass 5.6kg. It gets imbedded in the block. The bullet-block system then moves
a distance 10.78m and comes to rest in a time of 4.5 seconds.
vms
855
5.6kg
7.1 Calculate the combined speed of the bullet block system v-4.79 ms right
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Certain bacteria (such as aquaspirillum magnetotacticum) tend to swim toward the earth’s geographic north pole because they contain tiny particles, called magnetosomes, that are sensitive to a magnetic field. if a transmission line carrying 100 a is laid underwater, at what range of distances would the magnetic field from this line be great enough to interfere with the migration of these bacteria? (assume that a field less than 5% of the earth’s field would have little effect on the bacteria. take the earth’s field to be 5.0 * 10-5 t, and ignore the effects of the seawater.)