Answer:
<u>0.04 °C⁻¹</u>
Explanation:
First, we need to calculate linear expansivity, then after finding that value, we can move on to finding the area expansivity.
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Finding Linear Expansivity :
⇒ α = Final length - Original length / (Original length × ΔT)
⇒ α = 9 - 4 / (4 × 70 - 20)
⇒ α = 5 / 5 × 50
⇒ α = <u>0.02</u>
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Finding Area Expansivity :
⇒ Area Expansivity = 2 × Linear Expansivity
⇒ β = 2 × α
⇒ β = 2 × 0.02
⇒ β = <u>0.04 °C⁻¹</u>
Answer:
v = 478.26 km/h
Explanation:
The question is "find in km.h the speed of a tiger that runs 550 km in 69min"
Distance, d = 550 km
Time, t = 69 min = 1.15 h
We need to find the speed of the tiger. The speed of an object is equal to the total distance covered divided by time taken. So,

So, the speed of the tiger is 478.26 km/h.
Answer:
Explanation:
Force between two charges is given by the following expression
F =
Q₁ and Q₂ are two charges and d is distance between two.
.1 = 
If Q₁ becomes three times , force will become 3 times . Hence force becomes .3 N in the first case.
Force F = .3 N
If charge becomes one fourth , force also becomes one fourth .
F= 
= .025 N.
The answer is D interferometry