This problem involves calculating the additional distance a body needs to fall to double its velocity, starting from rest.
We use the kinematic equation relating final velocity (\(v_f\)), initial velocity (\(v_i\)), acceleration (\(a\)), and distance (\(d\)):
\(v_f^2 = v_i^2 + 2ad\)
Here, the acceleration is due to gravity (\(a = g\)), and the body starts from rest (\(v_i = 0\)).
Let the velocity after falling a distance '\(h\)' be '\(v\)'. Using the kinematic equation:
\(v^2 = 0^2 + 2gh\)
\(v^2 = 2gh \quad \quad (1)\)
We want the velocity to become '\(2v\)'. Let the total distance fallen to achieve this velocity be '\(H\)'.
Using the same kinematic equation:
\((2v)^2 = 0^2 + 2gH\)
\(4v^2 = 2gH \quad \quad (2)\)
Substitute the value of '\(v^2\)' from equation (1) into equation (2):
\(4(2gh) = 2gH\)
\(8gh = 2gH\)
Divide both sides by '\(2g\)':
\(H = \frac{8gh}{2g}\)
\(H = 4h\)
This '\(H\)' is the total distance fallen. The question asks for the *further* distance needed after the initial fall of '\(h\)'.
Further Distance = Total Distance (\(H\)) - Initial Distance (\(h\))
Further Distance = \(4h - h = 3h\)
Therefore, the body has to fall an additional distance of 3 times '\(h\)'.
A particle experiences constant acceleration for 20 s after starting from rest. If it travels a distance X 1, in the first 10 s and distance X 2in the remaining 10 s, then which of the following is true?
Which of the following is an equation of motion?
I. u = v + at
II. 2as = v 2– u 2
If the distance travelled by a body in the $n^{th}$ second is given by $(7 + 5n)$ m, then find the initial velocity and acceleration of the body respectively.
Which of the following is an equation of motion?
I. u = v + at
II. 2as = v 2– u 2