A woman starts from her home at 9.00 am, walks with a speed of `5 km h^(-1)` on a straight road up to her office 2.5 km away, stays at the office up to 5.00 pm, and returns home by an auto with a speed of `25 km h^(-1)`. Choose suitable scales and plot the x-t graph of her motion.

A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km h^(-1). Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km h^(-1). What is the (a) magnitude of average velocity, and (b) average speed of the man over the interval of time (i) 0 to 30 min, (ii) 0 to 50 min, (iii) 0 to 40 min ? [Note: You will appreciate from this exercise why it is better to define average speed as total path length divided by time, and not as magnitude of average velocity. You would not like to tell the tired man on his return home that his average speed was zero !]

A car is moving with at a constant speed of 60 km h^(-1) on a straight road. Looking at the rear view mirror, the driver finds that the car following him is at a distance of 100 m and is approaching with a speed of 5 km h^(-1) . In order to keep track of the car in the rear, the driver begins to glance alternatively at the rear and side mirror of his car after every 2 s till the other car overtakes. If the two cars were maintaining their speeds, which of the following statement (s) is // are correct?

A man walks on a straight road form his home to a market 2.5 km away with speed of 5 (km)/(hr) . Finding the market closed, he instantly turns and walks back home with a speed of 7.5 (km)/(hr) . The average speed of the man over the intervel of time 0 to 40 min is equal to

A bus decreases its speed from 80 km h^(-1) to 60 km h^(-1) in 5s. Find the acceleration of the bus.

A girl riding a bicycle along a straight road with a speed of 5 ms^(-1) throws a stone of mass 0.5 kg which has a speed of 15 ms^(-1) with respect to the ground along her direction of motion. The mass of the girl and bicycle is 50 kg. Does the speed of the bicycle change after the stone is thrown ? What is the change in speed, if so

A man of height 2 metres walks at a uniform speed of 5 km/h away from a lamp post which is 6 metres high. Find the rate at which the length of his shadow increases.