The climate<span> was generally warmer and more humid than today, probably because of very active volcanism associated with unusually high rates of seafloor spreading.
</span><span>The first placental mammals appeared at the beginning of the Cretaceous. The Cretaceous saw the rise and extinction of the toothed birds, Hesperornis and Ichthyornis. The earliest fossils of birds resembling loons, grebes, cormorants, pelicans, flamingos, ibises, rails, and sandpipers were from the Cretaceous.</span>
Answer:
I think it has to do something with their ionizations... not entirely sure though.
Explanation:
Answer:
Explanation:
Given that,
Mass of the thin hoop
M = 2kg
Radius of the hoop
R = 0.6m
Moment of inertial of a hoop is
I = MR²
I = 2 × 0.6²
I = 0.72 kgm²
Period of a physical pendulum of small amplitude is given by
T = 2π √(I / Mgd)
Where,
T is the period in seconds
I is the moment of inertia in kgm²
I = 0.72 kgm²
M is the mass of the hoop
M = 2kg
g is the acceleration due to gravity
g = 9.8m/s²
d is the distance from rotational axis to center of of gravity
Therefore, d = r = 0.6m
Then, applying the formula
T = 2π √ (I / MgR)
T = 2π √ (0.72 / (2 × 9.8× 0.6)
T = 2π √ ( 0.72 / 11.76)
T = 2π √0.06122
T = 2π × 0.2474
T = 1.5547 seconds
T ≈ 1.55 seconds to 2d•p
Then, the period of oscillation is 1.55seconds
