Answer:
a)mass = 300kg
b) no of atoms = 1.81 x 10^26atoms.
c)Fission Activity = 207Bq
d) no of fissions = 1.79 × 107 d^-1
Explanation:
a)mass= (3×10-4)(10^6kg) = 300kg
b) no of atoms = (300kg) X (6.022×10^23/kg) = 1.81 x 10^26atoms.
c)Fission Activity = (0.69)(300kg) = 207Bq
d) no of fissions = (207)(86400) = 1.79 × 107 d^-1
Answer:
3.53 second
Explanation:
The formula for the height is

When it hits the ground, the height is zero.
So, put h = 0 in the above equation




Take positive sign
t = 3.53 second.
Thus, the time taken to hit the ground is 3.53 second.
To determine the force that acts on the mass, just multiply the mass by the gravitational field. Using the given data,
F = (2.50 kg)(14 N/kg) = 35 N
Therefore, the force that acts on the mass is equal to 35 N.
The intensity ratio at point A and B will be 81:16.
<u>Explanation:</u>
Sound waves are known to get faded with increase in the distance. This is because, the intensity of the sound is inversely proportional to the square of the distance of the source from the observer. So, if an observer is standing greater distance from the source of the sound, he/she will find difficulty in hearing the sound.
So, as the distance between the source and observer increases, the intensity of the sound wave decreases.

As here two points A and B are located at 4 m and 9 m distance from the source, then the intensity of sound at A and B will be inversely proportional to their respective square of the distance as shown below.

Similarly,

So, the ratio of intensity at point A and B will be

Thus, the intensity ratio at point A and B will be 81:16.
The SI unit of mass is the kilogram, and
the SI unit of force is the Newton.