Class 9 Exam > Class 9 Questions > If the upward direction is taken as positive ...
Start Learning for Free
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.
- a)positive acceleration and negative velocity
- b)positive acceleration and positive velocity
- c)negative acceleration and positive velocity.
- d)negative acceleration and negative velocity
Correct answer is 'D'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Verified Answer
If the upward direction is taken as positive what is the sign of veloc...
Both velocity and acceleration are in the downward direction. Thus, they will be considered negative as they are vectors and the upward direction is positive.
View all questions of this test
Most Upvoted Answer
If the upward direction is taken as positive what is the sign of veloc...
The sign convention for velocity and acceleration is determined by the chosen coordinate system. In this case, the upward direction is taken as positive. Let's analyze the motion of a body falling freely from a height using this convention.
1. Initial Conditions:
- The body is at rest when it is dropped from a height.
- The initial velocity is zero.
2. Motion during Free Fall:
- As the body falls freely, it accelerates downwards due to the force of gravity.
- The acceleration remains constant throughout the motion and is equal to the acceleration due to gravity (9.8 m/s^2).
- The velocity of the falling body increases in the downward direction as time progresses.
3. Sign of Velocity:
- Since the upward direction is taken as positive, the velocity of the falling body will be negative.
- This is because the body is moving in the downward direction, opposite to the positive direction.
4. Sign of Acceleration:
- The acceleration due to gravity acts in the downward direction.
- Therefore, the acceleration will also be negative.
- The negative sign indicates that the acceleration is acting in the opposite direction to the positive direction defined by the coordinate system.
5. Final State:
- When the body reaches the ground, its velocity will be at its maximum, which is negative.
- The acceleration remains negative as long as the body is falling.
Hence, it can be concluded that the correct answer is option D: negative acceleration and negative velocity. This is because the body is falling in the negative direction (opposite to the positive direction defined by the coordinate system) and its velocity and acceleration are both negative.
1. Initial Conditions:
- The body is at rest when it is dropped from a height.
- The initial velocity is zero.
2. Motion during Free Fall:
- As the body falls freely, it accelerates downwards due to the force of gravity.
- The acceleration remains constant throughout the motion and is equal to the acceleration due to gravity (9.8 m/s^2).
- The velocity of the falling body increases in the downward direction as time progresses.
3. Sign of Velocity:
- Since the upward direction is taken as positive, the velocity of the falling body will be negative.
- This is because the body is moving in the downward direction, opposite to the positive direction.
4. Sign of Acceleration:
- The acceleration due to gravity acts in the downward direction.
- Therefore, the acceleration will also be negative.
- The negative sign indicates that the acceleration is acting in the opposite direction to the positive direction defined by the coordinate system.
5. Final State:
- When the body reaches the ground, its velocity will be at its maximum, which is negative.
- The acceleration remains negative as long as the body is falling.
Hence, it can be concluded that the correct answer is option D: negative acceleration and negative velocity. This is because the body is falling in the negative direction (opposite to the positive direction defined by the coordinate system) and its velocity and acceleration are both negative.
Free Test
FREE
| Start Free Test |
Community Answer
If the upward direction is taken as positive what is the sign of veloc...
According to co-ordinate system the values which are towards the right hand side and the ones which are on the upper side are considered positive and the values on the left hand side and downward direction are considered negative and as acceleration due to gravity is in downward direction and velocity is also towards downward direction both are taken as negative
Attention Class 9 Students!
To make sure you are not studying endlessly, EduRev has designed Class 9 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 9.
|
Explore Courses for Class 9 exam
|
|
Similar Class 9 Doubts
Top Courses for Class 9View all
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer?
Question Description
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? for Class 9 2024 is part of Class 9 preparation. The Question and answers have been prepared according to the Class 9 exam syllabus. Information about If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? covers all topics & solutions for Class 9 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer?.
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? for Class 9 2024 is part of Class 9 preparation. The Question and answers have been prepared according to the Class 9 exam syllabus. Information about If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? covers all topics & solutions for Class 9 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer?.
Solutions for If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 9.
Download more important topics, notes, lectures and mock test series for Class 9 Exam by signing up for free.
Here you can find the meaning of If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer?, a detailed solution for If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? has been provided alongside types of If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.a)positive acceleration and negative velocityb)positive acceleration and positive velocityc)negative acceleration and positive velocity.d)negative acceleration and negative velocityCorrect answer is 'D'. Can you explain this answer? tests, examples and also practice Class 9 tests.
|
|
Explore Courses for Class 9 exam
|
|
Suggested Free Tests
Test: The Fundamental Unit of Life- Case Based Type Questions- 1
Test | 10 questions
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup