Mechanics.physics help

while working in non-inertial frames of reference,a pseudo force needs to be applied to the object under consideration,to convert the non-inertial frame into inertial frame so that newton's second law can be applied..can you tell me as to why there is a need to apply a pseudo force and how does it help in solving the problem?

Suppose there is a net zero force on a block and it is at rest relative to an inertial frame. Next suppose you view the block from a reference frame accelerating along the x-axis. In this frame the block has an acceleration, but no apparent force on it. So Newtons Laws would not be valid in the accelerating frame.
Similarly, suppose you were in a car going around a circular track. You place a ball on the seat and it rolls toward the door, with no apparent force on it. Again, not obeying Newton.
In these, and similar cases, it is sometimes convienient to simply make up a force "pseudo force" also called an "inertial force" to account for the observed acceleration.
By doing this you can often proceed to solve more complicated problems, that include real forces, by applying Newton's Laws as usual. So you're trying to solve a complicated problem, with real forces, from an accelerated frame and its not working out. All you need to do is add the pseudo force into the problem, along with the real forces, and everything then works out fine.