Answer:
more time to change the momentum of falling rocks
Explanation:
Momentum is related to "mass in motion." So, if an object is moving, then it has momentum as it has its mass in motion. The amount of momentum is dependent upon how much and how fast the object is moving.
If an object is moving slowly, it means that the object is losing momentum.
Nets used to catch falling boulders on the side of rocky hillside roadways are more effective than rigid fences because their breakage is reduced by more time to change the momentum of falling rocks.
Answer:
The right solution is "
".
Explanation:
Given that,
q = 0.50 nC
d = 900 mm
As we know,
⇒ 
By putting the values, we get
⇒ 
⇒ 
⇒
Answer:
I didn't understand that all please tell me in Russia
Answer: 1.12 m
Explanation:
This situation is related to parabolic motion, hence we can use the following equations:
(1)
(2)
Where:
is the ball final height (when it hits the ground)
is the ball initial height
is the initial velocity
is the angle at which the ball was launched
is the time
is the acceleration due gravity
is the horizontal distance the ball travels
Rewriting (1) with the given values:
(3)
Multiplying all the eqquation by -1 and rearranging:
(4)
So, since we have a quadratic equation here (in the form of
, we will use the quadratic formula to find
:
(5)
Where
,
,
Substituting the known values and choosing the positive result of the equation, we have:
(6)
Now, substituting (6) in (2):
(7)
(8) This is the horizontal distance at which the ball hits the ground.
Answer:
Electrons.
Explanation:
Electricity was discovered before the discovery of electrons by J.J Thompson in 1896. Before the electron, it was thought that it is the positive ions that move through the wire and carry current—that's why today the conventional current represents the flow of positive charges.
After J.J Thompson's discovery of the electrons, it was realized that it is the electrons that actually carry the current through the conductor. But changing the direction of the conventional current didn't seem appropriate, and that's why the convention continues to be used to this day—reminding us that once it were the positive ions that were thought to carry the current.