Answer:Alpha decay, type of radioactive disintegration in which some unstable atomic nuclei dissipate excess energy by spontaneously ejecting an alpha particle.
Explanation:
Answer:
Velocidad final, V = 40 m/s
Explanation:
Dados los siguientes datos;
Aceleración = 5 m/s²
Velocidad inicial = 0 m/s (ya que comienza desde el reposo)
Tiempo = 8 segundos
Para encontrar la velocidad final, usaríamos la primera ecuación de movimiento;
Dónde;
- V es la velocidad final.
- U es la velocidad inicial.
- a es la aceleración.
- t es el tiempo medido en segundos.
Sustituyendo en la fórmula, tenemos;

<em>Velocidad final, V = 40 m/s</em>
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.
Answer:
v = 14 m/s
= 31.3 mph
The answer would be the same if the mass of the car were 2000 kg
Explanation:
Let V be the final velocity of the car after skidding, and v be the initial velocity of the car. Let a be the acceleration of the car and Δx be the distance the car travels after applying brakes (length of the skid marks). Let Fk be the force of friction between the tyres and the road. Let N be the normal force exerted on the car and μ be the co efficient of kinetic friction.
V^2 = v^2 + 2×a×Δx
Now V, the final velocity is zero as the car stops
0 = v^2 + 2×a×Δx
v^2 = -2×a×Δx
v =√-2×a×Δx .....*
Now applying Newton's Second Law
Fnet = m×a
-Fk = m×a
-μ×N = m×a
-μ×m×g = m×a (The mass cancels out)
a = -μ×g
Substituting the value of a back to equation *
v = √-2×(-μ×g)×Δx
v = √-2×(-0.5×9.8)×20
v = 14 m/s
Therefore the speed the car was travelling with v = 14 m/s
which is equal to 31.3 mph
Now if you were to change the mass of the car to 2000 kg the value for v would still be the same. As it is seen above mass cancels out so it does not influence or affect the value of the velocity obtained.