Search Results<span>By simply wrapping wire that has an electrical current running through it around a nail, you can make an electromagnet. When the electric current moves through a wire, it makes a magnetic field. ... You can make a temporary magnet by stroking apiece of iron or steel (such as a needle) along with a permanent magnet.
Hope This Helps!</span>
Force = change of momentum / time taken
Force = (90x3)/0.6
Tides are incredibly vital. They are controlled by the gravity of the moon pivoting the earth on a 28 day cycle, pulling the water round the world.
On the off chance that you are a mariner you require tide tables for two vital reasons. The first is that the water may not be sufficiently profound to get in and out of harbor or, say, over a sand bank, until specific times of day.
Another reason is that to spare time and power we need to cruise with the active tide on the off chance that it is going our path - to cruise against the tide can mean really going in reverse - I have seen vast cruising vessels beating to windward against the tide on the western ways to deal with the Solent going actually in reverse, (however they had forward speed through the water). Terrible arranging!
Since it is a 28 day cycle and there are 13 heaps of 28 days in a year the tides shift day by day with respect to when it is high tide and low tide, More than that we have neap tides when the highs and lows are less and spring tides when they are most prominent. These rely on upon the periods of the moon.
On the environment front they wash into and through ocean growth circulating air through the plants and ocean life and mix up silt to clean the base of the shoreline and channels and estuaries and invigorate pools that stay on the shoreline for other plant and creature life. This is one justifiable reason motivation behind why tidal hindrances will be a calamity for beach front life since this will be lost to power era. A similar thing applies to wave control and, ashore, wind control - there will be a substantial environmental cost to any maintained or pragmatic utilization of vitality that is in truth not "renewable" - we will upset a fragile adjust of nature that will do much more harm than carbon ever could (on the off chance that it was doing any harm now, which I question)
Tides are not such a great amount of checked as anticipated but rather perilous high tides can happen at the most elevated spring tide, with the twist inland and low gaseous tension - everything pushes the water advance up the shoreline and cause harm and flooding.
Answer:
V₁ = √ (gy / 3)
Explanation:
For this exercise we will use the concepts of mechanical energy, for which we define energy n the initial point and the point of average height and / 2
Starting point
Em₀ = U₁ + U₂
Em₀ = m₁ g y₁ + m₂ g y₂
Let's place the reference system at the point where the mass m1 is
y₁ = 0
y₂ = y
Em₀ = m₂ g y = 2 m₁ g y
End point, at height yf = y / 2
= K₁ + U₁ + K₂ + U₂
= ½ m₁ v₁² + ½ m₂ v₂² + m₁ g 
+ m₂ g
Since the masses are joined by a rope, they must have the same speed
= ½ (m₁ + m₂) v₁² + (m₁ + m₂) g
= ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
How energy is conserved
Em₀ =
2 m₁ g y = ½ (m₁ + 2m₁) v₁² + (m₁ + 2m₁) g
2 m₁ g y = ½ (3m₁) v₁² + (3m₁) g y / 2
3/2 v₁² = 2 g y -3/2 g y
3/2 v₁² = ½ g y
V₁ = √ (gy / 3)
Solution :
The distance between the starting point and the end point, 
= 10 light years
But due to the relativistic motion of Bob and Charlie, the distance will be reduced following the Lorentz contraction. The contracted length will be different since they are moving with different speeds.
For Bob,
Speed of Bob's rocket with respect to Alice, 
So the distance appeared to Bob due to the length contraction,
Therefore, the time required to finish the race by Bob is
= 10.143 year
For Charlie,
Speed of Charlie's rocket with respect to Alice, 
So the distance appeared to Charlie due to the length contraction,
The time required to finish the race by Charlie is
= 5.77 year
