Question

Read the following statements and state whether they are True or False:
i) If $u$ and $a$ both are negative, motion is only retarded.
ii) If $u$ is negative but $a$ is positive, then displacement of the particle can never be positive.
iii) If u is positive but $a$ is negative particle comes to rest for a moment at some time but if $u$ is negative and $a$ positive it never comes to rest.

• A. F, F, F
• B. T, T, T
• C. T, F, T
• D. F, T, F

Answer 1

The correct option is A F, F, F

If both $u$ and $a$ are in the same direction then $u$ increases in direction decrease to zero then increase in direction of $a$.

So on the basis of the above statement, we come to a conclusion that all three statements are false.

For i) Velocity will increase in negative a direction always as initial velocity is also in -a direction.

For ii) First, $u$ decreases to zero then increases in the positive direction and keep on moving in the positive direction so ultimately will go the positive direction.

iii) Opposite sign of $u$ and a means at least one time $u$ will become zero.