Answer:
Friction, normal force, and weight
Explanation:
If the book slows down, it means that there must be friction acting in the opposite direction of the direction the book is moving in.
Weight is caused by the gravitational pull of the Earth on the book, and normal force is the table pushing the book up because the book is pushing down on the table (3rd law.)
Note that weight and normal force is not the 3rd law action-reaction pair. The pair is the force of the book on the table and the force of the table on the book.
Answer:
Explanation:
in a room with no windows that way it doesnt shatter. Usually a closet... or if you have a basement.sorry but that applies to all them
Answer: Copper and oxygen
Explanation:
Copper and oxygen shares the ionic bond. As we know that ionic bond is the most strongest bond. Here is the order:
Hydrogen bond< Metallic bond< Ionic bond.
That means order in terms of increasing bond strength is :
Hydrogen and hydrogen< Copper and copper< Copper and oxygen.
Answer:
Δ
= 84 Ω,
= (40 ± 8) 10¹ Ω
Explanation:
The formula for parallel equivalent resistance is
1 /
= ∑ 1 / Ri
In our case we use a resistance of each
R₁ = 500 ± 50 Ω
R₂ = 2000 ± 5%
This percentage equals
0.05 = ΔR₂ / R₂
ΔR₂ = 0.05 R₂
ΔR₂ = 0.05 2000 = 100 Ω
We write the resistance
R₂ = 2000 ± 100 Ω
We apply the initial formula
1 /
= 1 / R₁ + 1 / R₂
1 /
= 1/500 + 1/2000 = 0.0025
= 400 Ω
Let's look for the error (uncertainly) of Re
= R₁R₂ / (R₁ + R₂)
R’= R₁ + R₂
= R₁R₂ / R’
Let's look for the uncertainty of this equation
Δ
/
= ΔR₁ / R₁ + ΔR₂ / R₂ + ΔR’/ R’
The uncertainty of a sum is
ΔR’= ΔR₁ + ΔR₂
We substitute the values
Δ
/ 400 = 50/500 + 100/2000 + (50 +100) / (500 + 2000)
Δ
/ 400 = 0.1 + 0.05 + 0.06
Δ
= 0.21 400
Δ
= 84 Ω
Let's write the resistance value with the correct significant figures
= (40 ± 8) 10¹ Ω
I would say A not 100℅ thou