Answer:
72,300 years.
Explanation:
- Initial mass of this sample: 504 grams;
- Current mass of this sample: 63 grams.
What's the ratio between the current and the initial mass of this sample? In other words, what fraction of the initial sample hasn't yet decayed?
.
The value of this fraction starts at 1 decreases to 1/2 of its initial value after every half-life. How many times shall 1/2 be multiplied to 1 before reaching 1/8? . It takes three half-lives or years to reach that value.
In certain questions the denominator of the fraction is large. It might not even be an integer power of 2. The base-x logarithm function on calculators could help. Evaluate
to find the number of half-lives required. In case the base-x logarithm function isn't available, but the natural logarithm function is, apply the following expression (derived from the base-changing formula) to get the same result:
.
Answer:
Among force and impulse, There is a lesser calculation for impulse. Also, it has same dimensions as momentum. Hence that is most closely related.
Answer:
The coefficient of kinetic friction = 0.026
Explanation:
An 56 kg sled is being pulled across the snow, at constant speed,by a horizontal force of 15 N.
Here we have to note that the weight is pulled at a constant speed . This means that the net force acting on the weight is zero.
The external force acting on the body is in the forward direction and the friction acts in the backward direction.
Friction increases as the mass of the body increases.
Friction =
We now equate this to the external force of 15 N.
15 =
=
= 0.026
The coefficient of kinetic friction = 0.026
Answer:
After the colision, the stationary electron's momentum is given as:
P = 2.7328 x 10^(-25) kg m/s
The direction of momentum is the same as the direction of velocity of the electron.
Explanation:
In an Isolated system, when an object moving at some velocity v collides head on with a stationary object of equal mass. There velocities are exchanged.
This means that the first electron will become stationary and the electron which was stationary initially will start moving at a velocity of 3*10^(5)m/s in the same direction as the first electron.
Post collision momentum of the stationary electron:
V = 3 x 10^5 m/s
m = 9.1093 x 10^(-31) kg
Momentum = P = mV = 9.1093 x 10^(-31) x 3 x 10^5
P = 2.7328 x 10^(-25) kg m/s
The direction of momentum is the same as the velocity of the electron.