choose 2 correct option about motion in a straight line.
1. if a vechile has a zero velocity it must be stationary 2.the graph of position against time has to be a st.line 3.acceleration is the rate of change of speed 4.velocity is the rate of change of position 5.a reversing vechile must have negative velocity 6.two vechiles travelling at the same speed at the same instant of time on the same road must have the same velocity.
The correct options about motion in a straight line are:
1. If a vehicle has zero velocity, it must be stationary: This statement is correct. Velocity is defined as the rate of change of displacement, and if the velocity is zero, it means there is no change in displacement over time, indicating that the vehicle is stationary.
3. Acceleration is the rate of change of speed: This statement is correct. Acceleration is defined as the rate of change of velocity with respect to time. In the case of motion in a straight line, where the direction remains constant, acceleration is equal to the rate of change of speed.
2. The graph of position against time has to be a straight line: This statement is incorrect. The graph of position against time may or may not be a straight line, depending on the nature of motion. For example, if the object is moving with constant velocity, the graph would be a straight line, but if the object is accelerating or decelerating, the graph would be curved.