10s
5s
4s
2s
Correct answer is D
u = , H = 20, g = 10
From equation of motion under gravity
H = ut ± \(\frac{1}{2}\)gt2, It is falling so g is +ve
H = 0 + \(\frac{1}{2}\)gt2
H = \(\frac{1}{2}\)gt2
2H = gt2
\(\frac{2H}{g}\) = t2
t = \(\frac{\sqrt{2H}}{g}\)
= \(\frac{\sqrt {2 \times 20}}{10}\)
= √4
= 2s
The radiator of a motor car is cooled by ...
The frictional force between two bodies? ...
which of the following materials is a conductor? ...
The bob of a single pendulum has a mass of 0.02kg. Determine the weight of the bob [g = 10ms-2]...
For what value of 6 are the forces in the diagram above in equilibruim ...
The image in a pin-hole camera is ...