A car travels leftwards with decreasing velocity on a horizontal surface. Which of the following options about the direction of the acceleration, the direction of the net force, th... A car travels leftwards with decreasing velocity on a horizontal surface. Which of the following options about the direction of the acceleration, the direction of the net force, the kinetic energy of the car, and the sign of the net work done by external forces is correct for the situation described above?
Understand the Problem
The question is asking for the correct option regarding the direction of acceleration, net force, kinetic energy, and the net work done by external forces for a car traveling left with decreasing velocity. This involves concepts of physics related to motion and forces.
Answer
B: Direction of acceleration is right, direction of net force is right, kinetic energy is decreasing, and net work done is negative.
Answer for screen readers
The correct option is B.
Direction of acceleration: Right,
Direction of net force: Right,
Kinetic energy of the car: Decreasing,
Net work done by external forces: Negative.
Steps to Solve
- Understanding the Motion of the Car
The car is traveling left but with decreasing velocity. This indicates that the car is slowing down in the leftward direction.
- Direction of Acceleration
Since the car is decelerating (slowing down), the acceleration is in the opposite direction to the motion. Therefore, the direction of acceleration is to the right.
- Direction of Net Force
The net force acting on an object is in the direction of its acceleration. Since the acceleration is to the right, the direction of the net force is also to the right.
- Kinetic Energy of the Car
The kinetic energy of the car is given by the formula ( KE = \frac{1}{2}mv^2 ). Since the velocity is decreasing, the kinetic energy is also decreasing.
- Net Work Done by External Forces
The net work done is related to the change in kinetic energy. If the kinetic energy is decreasing, the net work done by external forces is negative.
The correct option is B.
Direction of acceleration: Right,
Direction of net force: Right,
Kinetic energy of the car: Decreasing,
Net work done by external forces: Negative.
More Information
This situation illustrates basic principles of kinematics and dynamics. When an object's velocity decreases, it experiences a net force in the opposite direction of travel, resulting in negative net work.
Tips
- Confusing the direction of acceleration with the direction of motion. Remember, acceleration points opposite to the direction of motion when an object is slowing down.
- Misinterpreting the implications of changing kinetic energy. Decreasing kinetic energy corresponds to negative work done by external forces.
AI-generated content may contain errors. Please verify critical information
