Answer:

Explanation:
Let the linear charge density of the charged wire is given as

here we can use Gauss law to find the electric field at a distance r from wire
so here we will assume a Gaussian surface of cylinder shape around the wire
so we have

here we have


so we have

The air that is inside a ship is much less dense than water. That's what keeps it floating! ... The closer the total density of the ship is to the density of the same volume of water, the greater the amount of the ship that will be in the water.
Answer:
The answer to your question: d.
Explanation:
a. The rate of change of momentum of an object is equal to the net force applied to the object.
This is the second a law of motion, so this answer is incorrect.
b. In the absence of a net force acting on it, an object moves with constant velocity.
This is the first Newton law of motion, so this option is not correct.
c. For any force, there always is an equal and opposite reaction force.
This is the third law of motion, so this is not the right option.
d. What goes up must come down.
Newton said this sentence, but is not part of the law of motion.
Explanation:
It is given that,
Length of the helicopter, l = 3.1 m
The helicopter rotates, the length of helicopter will become the radius of circular path, r = 3.1 m
Angular speed of the helicopter, 
(a) The centripetal acceleration in terms of angular velocity is given by :



(b) Let v is the linear speed of the tip. The relation between the linear and angular speed is given by :


v = 90.89 m/s

Hence, this is the required solution.
Answer:
93 o 39.
Explanation:
Hola.
En este caso, podemos resolver este problema por medio del planteamiento de las siguientes ecuaciones:
1. Definimos <em>x</em> como el primer dígito y <em>y</em> como el segundo, por lo tanto, como su suma es 12, escribimos:
<em>x</em> + <em>y</em> = 12
2. Ahora, dado que el primer dígito, x es el triple del segundo, escribimos:
<em>x</em> = 3 <em>y</em>
De este modo, podemos resolver para <em>y</em>:
3 <em>y</em> + <em>y</em> = 12
4 <em>y</em> = 12
<em>y</em> = 12 / 4
<em>y</em> = 3
Y para <em>x</em>:
<em>x</em> = 3 <em>y</em>
<em>x</em> = 3 * 3
<em>x</em> = 9
Así, el número puede ser 93 o 39.
¡Saludos!