Study the speed-time graph of a car given below and answer the following question. What type of motion is represented by O A ?

In the given speed-time graph of the car, the speed of the car changes from 0 m s - 1 to 40 m s - 1 , keeps the constant speed then again reduces the speed to 0 m s - 1 . By looking at the curve O A , we can see a uniformly accelerated motion as the slope is not changing throughout the time interval.

Study the speed-time graph of a car given below and answer the following question. What type of motion is represented by A B ?

By looking at the curve A B , the speed remains constant during the time interval which is 40 ms - 1 . In this position the body will have zero acceleration. So, we could simply say that AB represents uniform motion. In this case, we can calculate speed using the formula, speed = distance time .

Study the speed-time graph of a car given below and answer the following question. What type of motion is represented by BC?

By looking at the curve BC, we can see a uniformly decelerated motion as the slope is negative and constant throughout the time interval. In this case, the speed decreases and becomes zero.

Study the speed-time graph of a car given below and answer the following question. What is the acceleration of car from O to A ?

Acceleration of car from O to A , can be calculated using equation v = u + a t . From graph, u = 0 ms - 1 and v = 40 ms - 1 . Time period, t = 10 s . Therefore, 40 = 0 + a × 10 ⇒ a = 4 ms - 2 .

Study the speed-time graph of a car given below and answer the following question. What is the acceleration of car from A to B?

Acceleration of car from A to B is the slope of the line A B , but as we can see the speed is constant throughout the curve, A B shows a zero acceleration. Also, a = final velocity - initial velocity time = 40 - 40 20 = 0 ms - 2 .

Study the speed-time graph of a car given below and answer the following question. What is the retardation of car from B to C ?

The speed of the car is decreasing from the point B to C. So it is represented by a negative slope. The speed of the car at B is u = 40 m s - 1 and at C is v = 0 m s - 1 . The time taken by the car while moving from B to C is t = 50 - 30 = 20 s . Thus, the acceleration of the car is a = v - u t = 0 - 40 20 = - 2 m s - 2 . Hence, the retardation of the car while moving from B to C is 2 m s - 2 .

E M B I B E

Science for Ninth Class Part 1 Physics>Chapter 1 - Motion>Questions Based on High Order Thinking Skills (HOTS)

Lakhmir Singh and Manjit Kaur Solutions for Chapter: Motion, Exercise 10: Questions Based on High Order Thinking Skills (HOTS)

Author:Lakhmir Singh & Manjit Kaur

Lakhmir Singh Physics Solutions for Exercise - Lakhmir Singh and Manjit Kaur Solutions for Chapter: Motion, Exercise 10: Questions Based on High Order Thinking Skills (HOTS)

Attempt the free practice questions on Chapter 1: Motion, Exercise 10: Questions Based on High Order Thinking Skills (HOTS) with hints and solutions to strengthen your understanding. Science for Ninth Class Part 1 Physics solutions are prepared by Experienced Embibe Experts.

Questions from Lakhmir Singh and Manjit Kaur Solutions for Chapter: Motion, Exercise 10: Questions Based on High Order Thinking Skills (HOTS) with Hints & Solutions

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Science for Ninth Class Part 1 Physics>Chapter 1 - Motion>Questions Based on High Order Thinking Skills (HOTS)>Q 61

Three speed-time graphs are given below. Which graph represents the case of a trolley decelerating to a constant speed and then accelerating uniformly?