A brass ball is tied to a thin wire and swung so as to move uniformly in a horizontal circle. Which of the following statements in this regard is / are true? 1. The ball moves with constant velocity 2. The ball moves with constant speed 3. The ball moves

examrobotsa's picture

Submitted by examrobotsa on

Q: 1 (NDA-II/2015)
A brass ball is tied to a thin wire and swung so as to move uniformly in a horizontal circle.
Which of the following statements in this regard is / are true?
1. The ball moves with constant velocity
2. The ball moves with constant speed
3. The ball moves with constant acceleration
4. The magnitude of the acceleration of the ball is constant
Select the correct answer using the code given below:

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,10,23,3,8,12,10

keywords: 

{'constant velocity': [0, 0, 0, 2], 'constant acceleration': [0, 0, 0, 1], 'brass ball': [0, 0, 0, 1], 'acceleration': [0, 0, 2, 8], 'constant speed': [0, 0, 2, 5], 'ball': [1, 3, 13, 12], 'horizontal circle': [0, 0, 0, 1], 'magnitude': [0, 0, 3, 10], 'thin wire': [0, 0, 0, 1]}

The correct answer is option 4.

Let`s break down each statement to understand why option 4 is the correct answer:

1. The ball moves with constant velocity:

This statement is false because velocity is a vector quantity that includes both magnitude and direction. In this case, the direction of the ball is constantly changing as it moves in a horizontal circle, so the velocity is not constant.

2. The ball moves with constant speed:

This statement is true because speed is a scalar quantity that only considers the magnitude of the velocity. In a uniform circular motion, the speed remains constant as long as the radius of the circle and the time period of the movement remain constant.

3. The ball moves with constant acceleration:

This statement is false because acceleration is defined as the rate of change of velocity. In a uniform circular motion, the velocity is constantly changing due to the change in direction. Therefore, the ball experiences an acceleration towards the center of the circle, known as centripetal acceleration.

4. The magnitude of the acceleration of the ball is constant:

This statement is true. Although the direction of the acceleration changes continuously as the ball moves in a horizontal circle, the magnitude of the acceleration remains constant. The magnitude of the centripetal acceleration can be

Practice this on app