Advertisements
Advertisements
प्रश्न
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 ?
Advertisements
उत्तर
We have to find the deceleration. We have the following information given,
Initial velocity, (u) = 15 m/s
Final velocity, (v) = 0 m/s
Distance travelled, (s) = 18 m
Let the acceleration be (a)
We can calculate acceleration by using the 3rd equation of motion,
`a = (v^2 - u^2)/(2s)`
Put the values in above equation to find the deceleration,
a = (0-225)/(36)
⇒ `a =-6.25 "m/s"^2`
Thus , the deceleration is 6.25 `"m/s"^2`
APPEARS IN
संबंधित प्रश्न
What can you say about the motion of an object whose distance-time graph is a straight line parallel to the time axis?
What can you say about the motion of an object if its speed-time graph is a straight line parallel to the time axis?
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?
What does the slope of a distance-time graph indicate ?
Name the two quantities, the slope of whose graph give speed .
The slope of the distance-time graph at any point gives______.
What are the uses of the graphical study of motion?
Two students were asked to plot a distance-time graph for the motion described by Table A and Table B.
| Table A |
||||||
| Distance moved (m) | 0 | 10 | 20 | 30 | 40 | 50 |
| Time (minutes) | 0 | 2 | 4 | 6 | 8 | 10 |
| Table B |
||||||
| Distance moved (m) | 0 | 5 | 10 | 15 | 20 | 25 |
| Time (minutes) | 0 | 1 | 2 | 3 | 4 | 5 |
The graph given in figure is true for
If we denote speed by S, distance by D and time by T, the relationship between these quantities is ______.
Starting from A, Paheli moves along a rectangular path ABCD as shown in figure. She takes 2 minutes to travel each side. Plot a distance-time graph and explain whether the motion is uniform or non-uniform.
