Some substances look alike and the density can help you determine which is which. It also helps to tell which is heavier than the other.
Answer:
Alfred Wegener
Explanation:
Alfred Wegener is a german meteorologist who proposed the theory that the continents drifted, and he presented it to the German Geological Society on January 1912.
Answer:
The amount of electrons that flow in the given time is 3.0 C.
Explanation:
An electric current is defined as the ratio of the quantity of charge flowing through a conductor to the time taken.
i.e I =
...................(1)
It is measure in Amperes and can be measured in the laboratory by the use of an ammeter.
In the given question, I = 1.5A, t = 2s, find Q.
From equation 1,
Q = I × t
= 1.5 × 2
= 3.0 Coulombs
The amount of electrons that flow in the given time is 3.0 C.
Explanation:
The given data is as follows.
Resistance (R) = 1200 ohm, Area (A) =
m (as
)
Diameter (d) = 2.3 mm =
m
First, we will calculate the length as follows.
R =
Here,
= resistivity of aluminium = 
Putting the given values above and we will calculate the value of length as follows.
R =
1200 = 
L = 
As the circumference of circular wire = 
or, =
= 
And, number of turns will be calculated as follows.
No. of turns × Circumference = Length of wire
No. of turns × 
= 
Thus, we can conclude that
turns of wire are needed.