Base on my research, within 2 hours you have a number of atoms which remain.
N= N0*2^(-t/6.020 = N= N0*2^-0.33223= 07943 N0
So, the number of atoms that are being disintegrated is N0-N=N0*(1-0.79430)=0.2057 N0
It must be equal to 15 mCi = 15*3.7*10^7= 5.55*10^8 atoms
N0= 5.55*10*8/0.2057 = 2.698*10^9 atoms
Therefore, 2.698*10^9 atoms is the number of N0
Answer: D. 1,2,3
The paper pots used
in steamboat restaurants will not catch fire when in contact with the flame for
the heat is conducted quickly to the water because the paper is thin and the burning
temperature of the paper is much higher than the boiling point of water. Lastly, the texture of the paper is thick that it can withstand the temperature of the flame.
Answer:
-24 m/s
Explanation:
mass of the bowling ball = 3 kg
time (t) = 0.3 seconds
Force = 24 N
initial velocity u = ???
We know that;
Force = mass × acceleration (a)
So;
24 = 3 × a
a = 24/3
a = 8 m/s²
Also;
From equation of motion; acceleration is given by the relation;

if v = 0
then ;

24 = 0- u
u = -24 m/s
Thus; the initial velocity of the bowling ball when it first touched the mattress = -24 m/s
Answer:
3.4 mT
Explanation:
L = 0.53 m
i = 7.5 A
Theta = 19 degree
F = 4.4 × 10^-3 N
Let B be the strength of magnetic field.
Force on a current carrying conductor placed in a magnetic field.
F = i × L × B × Sin theta
4.4 × 10^-3 = 7.5 × 0.53 × B × Sin 19
B = 3.4 × 10^-3 Tesla
B = 3.4 mT
Ice at -25
Hope this helps
May God bless you and your family