Answer:
<u>Option "C":</u> "4.5 g"
Explanation:
N0 = 36 g, Let half-life is T.
t = 3 T, n is number of half lives = t / T = 3
<u>By using the decay law of radioactivity</u>
N / N0 = (1 / 2)^n
where
"N0" be the "initial amount"
"N" be the "amount left"
"n" be the "number of half-lives"
N / 36 = (1/2)^3
N / 36 = 1 / 8
N = 36 / 8 = 4.5 g
Answer:
A) Energy is tranferred from Joey to the water. The temperature of the water increases.
Explanation:
At first Joey jumps and gains a height above the water level of the pool, this way has an energy potential initial, as Joey falls into the water his speed is increased that is to say its energy potential is transformed into kinetic energy, and at the moment of impact with the water, this energy kinetic is transformed into heat which is transferred to the water. Therefore the temperature increment.
Note: This is one of the reasons why space agencies are studying spatial asteroids that are directed toward the earth, as these come with great kinetic energy, and great potential energy, if these are of a considerable size can cause catastrophic damage, even if they fall into the ocean, due to the large amount of energy which can cause the instantaneous evaporation of large amounts of water and collateral damage in other areas.
Answer:
a) + Q charge is inducce that compensates for the internal charge
b) There is no excess charge on the external face q_net = 0
c) E=0
Explanation:
Let's analyze the situation when a negative charge is placed inside the cavity, it repels the other negative charges, leaving the necessary positive charges to compensate for the -Q charge. The electrons that migrated to the outer part of the sphere, as it is connected to the ground, can pass to the earth and remain on the planet; therefore on the outside of the sphere the net charge remains zero.
With this analysis we can answer the specific questions
a) + Q charge is inducce that compensates for the internal charge
b) There is no excess charge on the external face q_net = 0
c) If we create a Gaussian surface on the outside of the sphere the net charge on the inside of this sphere is zero, therefore there is no electric field, on the outside
d) If it is very reasonable and this system configuration is called a Faraday Cage
e) We cannot apply this principle to gravity since there are no particles that repel, in all cases the attractive forces.
<h3><u>Full Question:</u></h3>
A 2-kg toy car accelerates from 5 to 10 m/s in 2 seconds. Find the applied force.
<h2><u>Answer:</u></h2>
Force applied is 
.
<h3><u>Explanation:</u></h3>
Force is defined as something which changes or tends to change the velocity of a body. And acceleration is defined as the rate of change of velocity of a body per time. Both of them are vector quantities.
The initial velocity of the body = 5 m/s.
The final velocity of the body = 10 m/s.
So the change in velocity = 10 - 5 m/s = 5m/s.
Time period = 2 seconds.
So acceleration =
= 
The force is defined as the product of mass and acceleration of the body.
Mass of body = 2 kg.
So, force applied = 
. =
.
