Answer: A. silicon and oxygen
Explanation:
The two most abundance elements in earth's crust are silicon and oxygen.
The most abundant element in earth's crust is Oxygen (O) which has a percentage composition of 46.6%. Oxygen is mainly present as silicates, carbonates, sulphates etc.
The second most abundant element in earth's crust is Silicon (Si) which has a percentage composition of 27.7%
. Silicon is present in the form of silicates.
The third most abundant element in earth's crust is aluminium (Al) which has a percentage composition of 8.1 %.
The fourth most abundant element in earth's crust is Iron (Fe) which has a percentage composition of 5.0 %.
Answer:
200 m\ s Ans .....
Explanation:
Data:
f = 200 Hz
w = 1.0 m
v = ?
Formula:
v = f w
Solution:
v = ( 200)(1.0)
v = 200 m\s <em>A</em><em>n</em><em>s</em><em> </em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em><em>.</em>
They will both hit the ground at the same time because gravitational acceleration for all objects is the same.
D = <span>
2.4 g/cm3We learned this in my physics class as well.
</span><span><span>
p = m/v</span></span>
Where:
p = density
m = mass
V = volume
So to find the density you solve 36/16
=2.4
Hope this helped. Have a great day!
Answer: A) False; B) False; C) True; D) False
Explanation: In order to explain this problem we have to take into account the expresion of the resistence of the condutor wire, which os given by:
R=ρ*L/A where ρ, L and A are the resistivity, length and area of the conductor.
As it can be seen, the resitence is inverse to the area so when the diameter decrease the resistance should increase its value. (A, C).
The resistivity does not depend on the length or diameter of the wire, only it depends on the material use to made the wire. (B,C and D).
