Second one:(adsbygoogle = window.adsbygoogle || []).push({});

Protons are projected at an angle of 30^{0}with an initial speed, given by V_{0}=8.2*10^{5}m/s, in a region of an electric field=-390EN/C, is present. The proton is to hit a point 1.27 mm in the pos-x direction from the launch point. Find (a) the two porjections angles (theta) that will result in a hit, and (b) the total time of flight for each of these two trajectories.j

Here is what I can get for this one.

(theta)=cos^{-1}(V_{0x}/V_{0})

(theta)=sin^{-1}(V_{0y}/V_{0})

F=q*E=-1.15*10^{-16}N

a=F/m=-6.89*10^{10}m/s^{2}

First one: Solved

on an analogue clock the minute hand aligns perfectly with the hour hand once and hour. 12:00 is the first time, when are the exact other times this happens. (Hint: in only happens 11 times, not 12 and the hour and minute hand constantly move)

time=3927.272727s*n

where n is the number of times the min hand has ligned up with the hour hand

ex:

1st time...........1:05:27.2727

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# Homework Help: 2 challenge problems for tommorrow(dec 7)

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