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:
The scientific defenision of work reveals its relationship to energy; whenever work is done, energy is transfered.
initially, the car is traveling at 5.0 m/s.
so, we know acceleration for changing velocity is :
a = (v-v
)/t ..........(i)
where v is the final velocity
v
is the initial velocity
t is the time taken to change velocity
Now, as per the question :
initial velocity, v
=5.0 m/s
final velocity, v =11 m/s
time taken, t = 3 s
putting the values in equation (i),
a = ( 11-5 )/3
a = 2 m/s²
Therefore, a, after 3 s, is <em>2 m/s².</em>
Answer:
The minumum speed the pail must have at its highest point if no water is to spill from it
= 2.64 m/s
Explanation:
Working with the forces acting on the water in the pail at any point.
The weight of water is always directed downwards.
The normal force exerted on the water by the pail is always directed towards the centre of the circle of the circular motion.
And the centripetal force, which keeps the system in its circular motion, is the net force as a result of those two previously mentioned force.
At the highest point of the motion, the top of the vertical circle, the weight and the normal force on the water are both directed downwards.
Net force = W + (normal force)
But the speed of this motion can be lowered enough to a point where the normal force becomes zero at the moment the pail reaches the highest point of its motion. Any speed lower than this value would result in the water spilling out of the pail. The water would not be able to resist the force of gravity.
At this point of minimum velocity,
Normal force = 0
Net force = W
Net force = centripetal force = (mv²/r)
W = mg
(mv²/r) = mg
r = 0.710 m
g = 9.8 m/s²
v² = gr = 9.8 × 0.71 = 6.958
v = √(6.958) = 2.64 m/s
Hope this Helps!!!
Answer:
We found out more about how the universe had started (Big Bang theory), how the planets were created and how stars are born.