Answer:
v = 3.78 m/s
Explanation:
given,
mass of the child = 36 Kg
length of the chain, r = 2.9 m
tension in each chain, T = 265 N
now,
Net force acting in the system
2 T - m g = m a
T is the tension in the chain
a is the acceleration in the normal direction
here,
now,
v² = 14.274
v = 3.78 m/s
speed of the child at the lowest point is equal to 3.78 m/s
Answer:If an object's speed changes, or if it changes the direction it's moving in,
then there must be forces acting on it. There is no other way for any of
these things to happen.
Once in a while, there may be a group of forces (two or more) acting on
an object, and the group of forces may turn out to be "balanced". When
that happens, the object's speed will remain constant, and ... if the speed
is not zero ... it will continue moving in a straight line. In that case, it's not
possible to tell by looking at it whether there are any forces acting on it
When the number of electrons striking the anode of an x-ray tube is increased, the <u>density</u> of emitted X-Rays increases.
Option: 1
<u>Explanation:</u>
As the electron speed increases, the heat radiation also increases from thermionic emission, which causes more heat and more X-ray release. X-rays are produced by an a vacuum tube called X-ray tube that uses more voltage to make the electrons accelerate which the hot cathode releases to a high velocity.
This high speed electrons meets in a collision with a metal target which is the anode, and thus create the X-rays. So, the electron number available and the time period set for their release from the filament determines how many x-rays are produced from the anode. Hence, more the number of electrons striking the anode,the more is the emission of x-rays.
Answer:
El conductor no puede evitar el choque.
Explanation:
Primero, convierta la velocidad del conductor a m / s:
1 km/h = 0.277778 m/s
126 km/h = 126 * 0.277778 = 35 m/s
La velocidad del automóvil es de 35 m / s.
El conductor presiona los frenos con una aceleración de -3.5 m / s² para evitar un choque a 150 m por delante.
Veamos qué distancia se moverá el automóvil después de que comience a desacelerar.
Utilizaremos una de las ecuaciones de movimiento lineal de Newton:
donde v = velocidad final = 0 m / s (el automóvil debe detenerse)
u = velocidad inicial = 35 m / s
a = aceleración = -3.5 m / s².
s = distancia recorrida
Por lo tanto:
Esto significa que el automóvil se detendrá a 175 m.
Por lo tanto, a esa velocidad y aceleración, el conductor chocará contra el árbol caído porque el automóvil no podrá detenerse antes de alcanzar la posición del árbol.