An energy crisis<span> is any significant (bottleneck; logistics; or price rise) in the supply of energy resources to an economy. In popular literature, it often refers to one of the energy sources used at a certain time and place, in particular those that supply national electricity grids or those used as fuel in vehicles.</span>
Answer:
<em>The distance is now 4d</em>
Explanation:
<u>Mechanical Force</u>
According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:
F = m.a
Where a is the acceleration of the object.
The acceleration can be calculated by solving for a:
Once we know the acceleration, we can calculate the distance traveled by the block as follows:
If the block starts from rest, vo=0:
Substituting the value of the acceleration:
Simplifying:
When a force F'=4F is applied and assuming the mass is the same, the new acceleration is:
And the distance is now:
Dividing d'/d:
Simplifying:
Thus:
d' = 4d
The distance is now 4d
Answer:
- Direct current is a current in which electrons flow in one direction only
- Alternating current is a current in which the direction of the electron flow reverses periodically - so, half a cycle forward, half a cycle backward
There are several advantages of using alternating currents for the transmission of electricity across a country, over large distances. The main advantages are:
- The voltage of alternating currents can be easily increased/decreased by using transformers. For instance, a transformer is used at the beginning of the transmission line to increase the voltage (electricity is transmitted at high voltage in order to reduce dissipated power), and then another transformer is used before the electricity enters the houses, in order to decrease the voltage. Transformers only work with alternating currents.
- It is easy to interrupt the flow of an alternating current, because its value naturally becomes zero every half a cycle, so this is useful in case the current must be interrupted.
Answer:
330.5 m
Explanation:
In this case, the object is launched horizontally at 30° with an initial velocity of 40 m/s .
The maximum height will be calculated as;
where ∝ is the angle of launch = 30°
vi= initial launch velocity = 40 m/s
g= 10 m/s²
h= 40²*sin²40° / 2*10
h={1600*0.4132 }/ 20
h= 661.1/2 = 330.5 m
<span>The egg doesn't break when it hits the sheet because the impact time is longer. Momentum means the egg is slowed rather than coming to an abrubt halt. The softer the object that the egg hits, the longer the time it takes to break. A sheet is so soft that the force is never high enough for the egg to break.</span>
