State whether speed is a scalar or a vector quantity. Give reason for your choice.

A cyclist travels a distance of 4 km from P to Q and then moves a distance of 3 km at right angle to PQ. Find his resultant displacement graphically.

A body starts to slide over a horizontal surface with an initial velocity of 0.5 m/s. Due to friction, its velocity decreases at the rate 0.105 m/s². How much time will it take for the body to stop?

If a sprinter runs a distance of 1000 metres in 9.83 seconds, calculate his average speed in km/h

Given below is the velocity-time graph for the motion of the car. What does the nature of the graph show? Also, find the acceleration of the car.