Answer with Explanation:
The direction of the electric field line at any point gives us the direction of the electric force that will act on a positive charge if placed at the point. We know that if we place a charge in an electric field it will experience a force, as we know that force is a vector quantity hence it requires both magnitude and direction for it's complete description. The direction of this electric force that acts on a charge is given by the direction of the electric field in the space. In case the charge is negatively charged electric force will act on it in the direction opposite to the direction of electric field at the point.
The unit conversion factors are always a power of ten. It is very easy to get different measurements quickly.
Answer:
Half life of the sample, 
Given:
Initial amount, N = 1679
Final count of amount, N' = 1336
Time elapsed, t = 4 min = 240 s
Solution:
Now, To calculate the half life, using the relation:
Now, substituting the given values in the above mentioned formula:
Taking log on both the sides:
ln(0.796) = \frac{4}{t_{\frac{1}{2}}}ln(0.5)
1.4 m/s im in 12th grade did this so this should be right
Answer:
<h2>To solve typical questions like this we can use law of conversation of linear momentum...which is</h2>
<h2>T.I.L.M.=T.F.L.M.</h2>
(Total initial linear momentum = total final linear momentum.)
<u>Momentum = mass × velocity</u>
<h2>T.I.L.M = T.F.L.M</h2>
180×4 + 120×0 = 180×0 + 120×V
(180 ×4)/120 = V
<h2>6Ms^-1 = v</h2>
