The Hubble constant H = 2.2 × 10−18 /s. An estimate of the age of the universe can be calculated from 1/H. What is this estimate?
Question 1 Report
The Hubble constant H = 2.2 × 10−18 /s.
An estimate of the age of the universe can be calculated from 1/H.
What is this estimate?
Answer Details
The age of the universe can be estimated from the reciprocal of the Hubble constant:
\[ t = \frac{1}{H} = \frac{1}{2.2 \times 10^{-18} \;\text{s}^{-1}} \]
Taking the reciprocal of \( 2.2 \times 10^{-18} \): the reciprocal of \( 2.2 \) is approximately \( 0.4545 \), and the reciprocal of \( 10^{-18} \) is \( 10^{18} \). Combining:
\[ t = 0.4545 \times 10^{18} = 4.5 \times 10^{17} \;\text{s} \]
A common mistake is to simply invert the sign of the exponent without inverting the coefficient, which would give \( 2.2 \times 10^{18} \) instead. Remember that \( 1/(a \times 10^n) = (1/a) \times 10^{-n} \), so both the number and the power of ten must be inverted.
Download The App On Google Playstore
Everything you need to excel in your exams
