Draw velocity-time graphs for the following situations
$(i)$ When body is moving with uniform velocity.
$(ii)$ When body is moving with variable velocity, but uniform acceleration.
$(iii)$ When body is moving with variable velocity, but uniform retardation.
$(iv)$ When body is moving with a variable velocity and variable acceleration.
The graph given below is the distance$-$time graph of an object.
$(i)$ Find the speed of the object during first four seconds of its journey.
$(ii)$ How long was it stationary ?
$(iii)$ Does it represent a real life situation ? Justify your answer.
An object is dropped from rest at a height of $150\, m$ and simultaneously another object is dropped from rest at a height $100 \,m$. What is the difference in their heights after $2\,\sec $ if both the objects drop with same accelerations ? How does the difference in heights vary with time ?
$(a)$ What is acceleration ? Write its $SI$ unit.
$(b)$ Draw velocity-time graph, when an object has
$(i)$ uniformly accelerated velocity
$(ii)$ uniformly retarded velocity.
What is the difference between uniform motion in a straight line and circular motion ?