Question

represent the following using velocity-time graph:a)object thrown vertically upwards.b)a train travelling in a straight line with a constant speed of 90 km/h​

Answer 1

The graphs are as shown in the picture.

-In the first part, object it thrown vertically upwards. It undergoes a projectile motion with angle of projection = 90 degrees

-It starts off with initial velocity u. As it goes up, the velocity decreases due to acceleration due to gravity acting downwards, until it finally reaches zero. The body then starts accelerating downwards and reaches the point from where it was thrown with the same velocity as u.

-The graph shows the maximum height at time t=t_g i.e., when the velocity is zero.

-second part is simple where the train is moving with constant speed in same direction i.e., the velocity(the magnitude and direction) does not change with time, hence it is a horizontal straight line.