Graphical representation of motion- Distance-Time Graphs:
Calculation Of Velocity By Using Distance Time Graph:
To calculate the velocity, let take two points A and B on the slope OB.
Draw one line parallel to y-axis and another parallel to x-axis from B.
Again draw a line parallel to y-axis and another parallel to x-axis from point A.
Let, line parallel to x-axis from point B cut at a point, S2 at y-axis.
Line parallel to x-axis from point A cut at point, S1 at y-axis.
Let, line parallel to y-axis from point B cut at t2 at x-axis.
Line parallel to y-axis from point A cut at t1 at x-axis.
Now, BC= Distance = S2 – S1 and AC = time = t2 – t1
We know that slope of the graph is given by the ratio of change in y-axis and change in X-axis.
Or, `"Slope" = "Change in y-axis" / "Change in x-axis"`
Thus, `"slope, AB"="BC"/"AC"`
Where, v= velocity, (s2−s1) = interval of distance and (t2−t1)= time interval
Thus, `"Velocity"="Distance" / "Time"`
Shaalaa.com | Motion part 10 (Graphical representation of motion)
What can you say about the motion of a body whose distance-time graph is a straight line parallel to the time axis ?
A cyclist is travelling at 15 m s-1. She applies brakes so that she does not collide with a wall 18 m away. What deceleration must she have ?
A car is travelling at 20 m/s along a road. A child runs out into the road 50 m ahead and the car driver steps on the brake pedal. What must the car’s deceleration be if the car is to stop just before it reaches the child ?
The graph given alongside shows the positions of a body at different times. Calculate the speed of the body as it moves from :
(1) A to B,
(2) B to C, and
(3) C to D.
Four cars A, B, C and D are moving on a levelled, straight road. Their distance-time graphs are shown in the given figure. Which of the following is the correct statement regarding the motion of these cars?
A student draws a distance-time graph for a moving scooter and finds that a section of the graph is horizontal line parallel to the time axis. Which of the following conclusion is correct about this section of the graph?
A driver of a car travelling at 52 km h−1 applies the brakes and accelerates uniformly in the opposite direction. The car stops in 5 s. Another driver going at 3 km h−1 in another car applies his brakes slowly and stops in 10 s. On the same graph paper, plot the speed versus time graphs for the two cars. Which of the two cars travelled farther after the brakes were applied?