Question

A football player is moving southward and suddenly turns eastward with the same speed to avoid an opponent. The force that acts on the player while turning is:

• A. along south-west
• B. along eastward
• C. along northward
• D. along north-east

Answer 1

The Correct Option is D

To understand the force acting on the player, let's analyze the situation step by step:

1. The football player is initially moving southward. In terms of directions, southward can be represented as a downward vector.
2. Suddenly, he changes his direction to move eastward while maintaining the same speed. Eastward can be represented as a vector pointing to the right.
3. This change in direction indicates an alteration in velocity, which necessarily involves acceleration, as acceleration is the rate of change of velocity. For a uniform circular motion, the acceleration is centripetal and acts towards the center of the circle.

The key point to note here is the change in velocity direction:
- The initial velocity vector is towards the south.
- The final velocity vector is towards the east.

To change direction from south to east, the player must experience a force (due to acceleration) that acts perpendicular to both the initial and final directions.

Using vector analysis:

• The initial velocity vector points south.
• The final velocity vector points east.
• The direction of change, or the resultant vector, is obtained through vector addition between the southward and eastward directions.
• This resultant vector points towards the north-east.

Thus, the net force experienced by the player while turning is along the north-east direction. This force can be considered as the centripetal force for the rounded path taken by the player.

Therefore, the correct answer is:

Option: along north-east