Explanation:
Given that,
The frequency of oscillation, f = 0.5 Hz
(a) Let the length of the pendulum string is l. So,
[tex]T=2\pi \sqrt{\dfrac{l}{g}}[/tex]
T is time period, T = 1/f
So,
[tex]l=\dfrac{(\dfrac{1}{f})^2g}{4\pi ^2}\\\\l=\dfrac{(\dfrac{1}{0.5})^2\times 9.8}{4\times 3.14 ^2}\\\\l=0.993\ m[/tex]
(b) When the elevator starts to accelerate upwards, new acceleration is a+g. If accelerating upward, the value of g has increased, because of inertia. So it will feel heavier and the period will decrease.
