Total distance to be covered = 1 km + 100 m = 1100 m (including both bridge and time)
Then, Speed=60 kmh^-1\(=60\times\frac{5}{18}ms^{-1}=\frac{50}{3}\ ms^{-1}\)
Then, time taken to cover this distance \(=\frac{1100}{\frac{150}{9}}s=66s\)

We know that when the object falls towards the Earth, it experiences acceleration due to gravity g = 9.8 m s^-2 downward. We can choose the coordinate system as shown in the figure. The acceleration is along the negative y direction.
\(\vec { a } =g(-\hat { j } )-g\hat { j } \)

Note that here the independent variable is 't' and the dependent variable is 'x'.
The required derivative is dx/dt = 0 + A₁ + 2A₂t.
The second derivative is d²x/d²t = 2A₂.

By comparing the components both sides, we can write
5 - 6 = 3T + T
 -1 = 4T
 T = \(-\frac{1}{4}\)

Consider a well without water, of some depth d. Take a small object (for example lemon) and a stopwatch. When you drop the lemon, start the stop watch. As soon as the lemon touches the bottom of the well, stop the watch. Note the time taken by the lemon to reach the bottom and denote the time as t.
Since the initial velocity of lemon u = 0 and the acceleration due to gravity g is constant over the well, we can use the equations of motion for constant acceleration.
s= \(ut+\frac { 1 }{ 2 } { at }^{ 2 }\)
Since u = 0 s=d, a = g (Since we choose the y-axis downwards),Then
d = \(\frac { 1 }{ 2 } { gt }^{ 2 }\)
Substituting g = 9.8 m s^-2 we get the depth of the well.
To estimate the error in our calculation we can use another method to measure the depth of the well. Take a long rope and hang the rope inside the well till it touches the bottom. Measure the length of the rope which is the correct depth of the well (d_correct).Then error = d_connect -d
relative error = \(\frac { { d }_{ corrct }-d }{ { d }_{ corrct } } \)
percentage of relative error =   \(\frac { { d }_{ corrct }-d }{ { d }_{ corrct } } \times 100\)
What would be the reason for an error, if any? Repeat the experiment for different masses and compare the result with d_correct every time.