A is the correct answer !!!
Explanation:
The equation of motion of an object is given by :

Where
t is the time in seconds
We need to find the time when the object hits the ground. When the object hits the ground, h(t) = 0
So,


On solving above equation using online calculator, t = 8 seconds. So, the object hit the ground after 8 seconds. Hence, this is the required solution.
Answer:

Explanation:
Given that
Length= 2L
Linear charge density=λ
Distance= d
K=1/(4πε)
The electric field at point P



So

Now by integrating above equation

Answer:
present
Explanation:
read doesn't change but write is in present tense