Answer:
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages. Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.
Explanation:
Mass of the crate, m = 68 kg
We need to find the resulting acceleration if :
(a) Force, P = 0
P = m a
⇒ a = 0
(b) P = 181 N



(c) P = 352 N



Hence, this is the required solution.
C. I did it bit i forgot how I did it
Answer:
83.6°
Explanation:
For the ray to be totally internally reflected, at the boundary, the angle of refraction is 90. Using the law of refraction where
n₁sinθ₁ = n₂sinθ₂ where n₁ = refractive index of prism = 1.5, θ₁ = critical angle in prism, n₂ = refractive index of air = 1 and θ₂ = refractive angle = 90°.
So, substituting these values into the equation,
n₁sinθ₁ = n₂sinθ₂
1.5 × sinθ₁ = 1 × sin90
1.5 × sinθ₁ = 1
sinθ₁ = 1/1.5
sinθ₁ = 0.6667
θ₁ = sin*(0.6667)
θ₁ = 41.8°
So, for total internal reflection, an incidence angle of 41.8° is required. So, a full convergence angle of 2 × 41.8° = 83.6° is required for the whole bundle of rays.
Answer:
The answer is B.
Explanation:
Given that the <em>current </em>(Ampere) in a series circuit is same so we can ignore it. We can assume that the total voltage is 60V and all the 3 resistance are different, 20Ω, 40Ω and 60Ω. So first, we have to find the total resistance by adding :
Total resistance = 20Ω + 40Ω + 60Ω
= 120Ω
Next, we have to find out that 1Ω is equal to how many voltage by dividing :
120Ω = 60V
1Ω = 60V ÷ 120
1Ω = 0.5V
Lastly, we have to calculate the voltage at R1 so we have to multiply by 20 (R1) :
1Ω = 0.5V
20Ω = 0.5V × 20
20Ω = 10V