A ball thrown up vertically upwards with a velocity of $45 \mathrm{m}/\mathrm{s}$, returns back to the thrower in $6 \mathrm{s}$. Assuming that there is no air friction, plot a graph between velocity and time. From the graph, calculate the average velocity.    

The given diagram shows velocity-time graphs of cars P and Q, starting from the same place and in the same direction.

Calculate the acceleration of car P in $\mathrm{m}/{\mathrm{s}}^2$

The given diagram shows velocity-time graphs of cars P and Q, starting from the same place and in the same direction.

Calculate the acceleration of car Q between $2 \mathrm{s} \mathrm{and} 5 \mathrm{s}$ in $\mathrm{m}/{\mathrm{s}}^2$. (Give the answer in two decimal points)

The given diagram shows velocity-time graphs of cars P and Q, starting from the same place and in the same direction.

Calculate at what time both the cars have the same velocity?

The given diagram shows velocity-time graphs of cars P and Q, starting from the same place and in the same direction.

Calculate which car is ahead after $10 \mathrm{s}$ and by how much?