`text(Motion in Accelerated Frames :)`
Till now we have restricted ourselves to apply Newton's laws of motion, only to describe observations that are made in an inertial frame of reference. In this part, we learn how Newton's laws can be applied by an observer in a non inertial reference frame. For example,consider a block kept on smooth surface of a compartment of train.
If the train accelerates, the block accelerates toward the back of the train. When observed from the train we may conclude based on Newton's second law `F=ma` that a force is acting the block to cause it to accelerate, but the Newton's second law is not applicable from this non- inertial frame. So we can not relate observed acceleration with the Force acting on the block.
If we still want to use Newton's second law we need to apply a pseudo force, acting in backward direction, i.e. opposite to the acceleration of non inertial reference frame. This force explains the motion of block towards the back of train. The fictious force is equal to `-mveca` where `a` is the acceleration of the non inertial reference frame. Fictitious force appears to act on an object in the same way as a real force, but real forces are always interactions between two objects, on the other hand there is no second object for a fictitious force.
Pseudo force, `vec(F_P)=-mvec(a_0)`
where `a_0` is acceleration of non inertial reference frame.
Thus, we may conclude that pseudo force is not a real force. When we draw the free body diagram of a mass, with respect to an inertial frame of reference we apply only the real forces (forces which are actually acting on the mass), but when the free body diagram is drown from a non-inertial frame of reference a pseudo force (in addition to all real forces) has to be applied to make the equation `vecF=ma_0` , valid in this frame also.
`text(Motion in Accelerated Frames :)`
Till now we have restricted ourselves to apply Newton's laws of motion, only to describe observations that are made in an inertial frame of reference. In this part, we learn how Newton's laws can be applied by an observer in a non inertial reference frame. For example,consider a block kept on smooth surface of a compartment of train.
If the train accelerates, the block accelerates toward the back of the train. When observed from the train we may conclude based on Newton's second law `F=ma` that a force is acting the block to cause it to accelerate, but the Newton's second law is not applicable from this non- inertial frame. So we can not relate observed acceleration with the Force acting on the block.
If we still want to use Newton's second law we need to apply a pseudo force, acting in backward direction, i.e. opposite to the acceleration of non inertial reference frame. This force explains the motion of block towards the back of train. The fictious force is equal to `-mveca` where `a` is the acceleration of the non inertial reference frame. Fictitious force appears to act on an object in the same way as a real force, but real forces are always interactions between two objects, on the other hand there is no second object for a fictitious force.
Pseudo force, `vec(F_P)=-mvec(a_0)`
where `a_0` is acceleration of non inertial reference frame.
Thus, we may conclude that pseudo force is not a real force. When we draw the free body diagram of a mass, with respect to an inertial frame of reference we apply only the real forces (forces which are actually acting on the mass), but when the free body diagram is drown from a non-inertial frame of reference a pseudo force (in addition to all real forces) has to be applied to make the equation `vecF=ma_0` , valid in this frame also.