Final answer:
To find the initial velocity from a velocity-time graph, locate the value on the y-axis where the graph starts at time zero. If the graph is a straight line, the y-intercept represents the initial velocity. For more complex graphs, focus on the segment of the graph at the beginning of the movement.
Step-by-step explanation:
Finding Initial Velocity from a Velocity-Time Graph
To find the initial velocity from a velocity-time graph, you should look at the value on the velocity axis (y-axis) at the exact point where the graph begins, which corresponds to time zero (t=0). In many cases, this will be where the time axis (x-axis) intersects with the graph. If the graph starts at any point above or below the origin, the value on the y-axis where it intersects will give you the initial velocity. If the graph depicts a line with a positive or negative slope, the initial velocity is given by the y-intercept of that line.
To further understand the concept, consider a velocity-time graph displaying constant acceleration. This graph is typically a straight line starting from the initial velocity and increasing or decreasing with time. For an object starting from rest, the initial velocity will be zero. Conversely, if the line has a nonzero y-intercept, this value represents the initial velocity of the object. It is important to interpret the graph correctly and to understand the context of the motion being described.
If the graph is more complicated, such as curves or multiple segments, focus on the segment that corresponds to the beginning of the movement.