**Suppose a snowy cricket is chirping when the temperature is 65.0 degrees Fahrenheit. How many oscillations does the radiation from a cesium-133 atom complete between successive chirps?**

**A. 7.98 × 107**

**B. 3.68 × 108**

**C. 4.78 × 109**

**D. 9.58 × 109**

**Answer:**

We have number of chirps in 13s **N = T- 40**

Here

Therefore **N = 65 - 40**

**= 25 Chirps in 13s**

Then time taken for successive chirps is

But time taken for radiation from a cesium-133 to complete 9,192,631,770 cycles is 1s.

Therefore number of oscillations in 1s is 9,192,631,770

Then the number of oscillations in 0.867s is

So, option C. is correct.