Share & grow the world's knowledge!
We want to connect the people who have knowledge to the people who need it, to bring together people with different perspectives so they can understand each other better, and to empower everyone to share their knowledge.
Fig. 4.27 shows a position-time graph of two objects A and B that are moving along the parallel tracks in the same direction. Do objects A and B ever have equal velocity? Justify your answer.
No, objects A and B never have equal velocity. In a position-time graph, the slope of the graph represents velocity. The graphs of A and B have different slopes throughout their motion. Although their position-time graphs intersect, this only means that they are at the same position at that instant.Read more
No, objects A and B never have equal velocity. In a position-time graph, the slope of the graph represents velocity. The graphs of A and B have different slopes throughout their motion. Although their position-time graphs intersect, this only means that they are at the same position at that instant. It does not mean that their velocities are equal. Therefore, their velocities are never equal.
For more NCERT Solutions of Class 9 Science Exploration Chapter 4 Describing Motion Around Us Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-4/
See lessA motorbike moving with initial velocity 28 m s⁻¹ and constant acceleration stops after travelling 98 m. Find the acceleration of the motorbike and the time taken to come to a stop.
For the motorbike, initial velocity u = 28 m s⁻¹, final velocity v = 0 and distance s = 98 m. Using v² = u² + 2as: 0 = 28² + 2(a)(98), giving a = −4 m s⁻². Using v = u + at: 0 = 28 − 4t, so t = 7 s. Thus, acceleration is −4 m s⁻² and stopping time is 7 s. For more NCERT Solutions of Class 9 SRead more
For the motorbike, initial velocity u = 28 m s⁻¹, final velocity v = 0 and distance s = 98 m. Using v² = u² + 2as:
0 = 28² + 2(a)(98), giving a = −4 m s⁻².
Using v = u + at: 0 = 28 − 4t, so t = 7 s. Thus, acceleration is −4 m s⁻² and stopping time is 7 s.
For more NCERT Solutions of Class 9 Science Exploration Chapter 4 Describing Motion Around Us Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-4/
See lessA car starts from rest and its velocity reaches 24 m s⁻¹ in 6 s. Find the average acceleration and the distance travelled in these 6 s.
The initial velocity of the car is u = 0 m s⁻¹, final velocity is v = 24 m s⁻¹ and time is t = 6 s. Average acceleration = (v − u)/t = (24 − 0)/6 = 4 m s⁻². Distance travelled = average velocity × time = [(u + v)/2] × t = [(0 + 24)/2] × 6 = 72 m. For more NCERT Solutions of Class 9 Science ExRead more
The initial velocity of the car is u = 0 m s⁻¹, final velocity is v = 24 m s⁻¹ and time is t = 6 s.
Average acceleration = (v − u)/t = (24 − 0)/6 = 4 m s⁻².
Distance travelled = average velocity × time = [(u + v)/2] × t = [(0 + 24)/2] × 6 = 72 m.
For more NCERT Solutions of Class 9 Science Exploration Chapter 4 Describing Motion Around Us Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-4/
See lessA girl is riding her scooter and finds that its speedometer reading is constant. Is it possible for her scooter to be accelerating and if so, how?
Yes, it is possible for the scooter to be accelerating even when its speedometer reading remains constant. Acceleration is the rate of change of velocity and velocity depends on both speed and direction. Therefore, if the scooter moves with constant speed but continuously changes its direction, itsRead more
Yes, it is possible for the scooter to be accelerating even when its speedometer reading remains constant. Acceleration is the rate of change of velocity and velocity depends on both speed and direction. Therefore, if the scooter moves with constant speed but continuously changes its direction, its velocity changes and the scooter is accelerating. For example, this occurs when the scooter moves along a circular path.
For more NCERT Solutions of Class 9 Science Exploration Chapter 4 Describing Motion Around Us Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-4/
See lessUnder what condition(s) is the: (i) magnitude of average velocity of an object equal to its average speed? (ii) magnitude of average velocity of an object zero while its average speed is not zero?
(i) The magnitude of average velocity is equal to average speed when an object travels along a straight-line path without changing its direction, so distance travelled equals the magnitude of displacement. (ii) The magnitude of average velocity can be zero when the object returns to its starting poiRead more
(i) The magnitude of average velocity is equal to average speed when an object travels along a straight-line path without changing its direction, so distance travelled equals the magnitude of displacement.
(ii) The magnitude of average velocity can be zero when the object returns to its starting point. Its displacement is then zero, but its total distance travelled is not zero, so its average speed remains non-zero.
For more NCERT Solutions of Class 9 Science Exploration Chapter 4 Describing Motion Around Us Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-4/
See less