River shore is located at distance
speed of the woman is given as
now the time taken by the woman to cover the distance is
for the same time interval the dog will run to and fro with speed 4.5 m/s
so the total distance moved by the dog is given by
<em>so the total distance that dog will move is 7200 m or 7.2 km</em>
Answer:
0.0000076 grams
Explanation:
We're given the half life of Tritium to be 12.3 years. In order to find out the amount of substabce remaining:
Let's first find how many 'half lives' are in 250 years.
Now what is half life? It means the time taken for a given quantity of an element to lose half it's mass.
So in 12.3 years we can find that The amount of 250 g of Tritium will be 250/2 = 125 g. In 24.6 years we'll have 125/2 = 62.5 g
So now we can devise a formula:
Where m is the remaining amount and n is th number of half lives in the time given.
Using this formula we can calculate:
Doing this calculation we get:
As we can see a very small value remains.