Question

Which of the following are not correct?
(i) The basic unit of time is second.
(ii) Every object moves with a constant speed.
(iii) Distances between two cities are measured in kilometers.
(iv) The time period of a given pendulum is not constant.
(v) The speed of a train is expressed in m/h.

Answer 1

(i) The basic unit of time is second - Correct
(ii) Every object moves with a constant speed - Not correct
(iii) Distances between two cities are measured in kilometers - Correct
(iv) The time period of a given pendulum is not constant - Not correct
(v) The speed of a train is expressed in m/h - Not correct