The velocity of a particle increases from $u$ to $v$ in a time $t$ during which the particle has uniform acceleration. Which of the following equation applies to the motion?

The velocity-time graph of an object is shown in the figure. Identify the correct statement(s) regarding this graph.

i) This is a non-uniform velocity-time graph of the object.

ii) The velocity of the object is increasing at the same rate during OP and QR.

iii) The velocity of the object is decreasing at the same rate during PQ and RT.

A boy takes $5 \mathrm{s}$ to reach each point from A to B, B to C and C to D as shown in the diagram. If $AB=BC=CD=20 \mathrm{m}$, then which of the following is correct when the body reaches D from A through BC?

Two racing cars of masses $m_1, m_2$ are moving in circles of radii $r_1, r_2$ respectively. Their speeds are such that each makes a complete circle in the same length of time $T$. The ratio of angular speed of the first car to the second car is :

The diagram shows the velocity-time graph of two moving cars $P,Q$. The graph indicates that 

i) The velocity of car $P$ is increasing at a decreasing rate from $40 \mathrm{s}- 45 \mathrm{s}$ in the same direction.

ii) Car $Q$ is moving with a constant acceleration from $0-20 \mathrm{s}$.

iii) Acceleration of the car $Q$ is not zero at any point during the whole journey.

iv) After $20 \mathrm{s}$, $P$ is behind $Q$.

Which of the following is correct?