Concept:Uniform retardation means the velocity of a body decreases by equal amounts in equal time intervals. So the velocity-time graph must be a straight line sloping downward.
Explanation:Acceleration is the rate of change of velocity. For uniform acceleration, the velocity-time graph is a straight line. Since retardation is negative acceleration, the acceleration is constant and negative:
a=tv−u<0.
This means as time increases, velocity decreases at a steady rate. Therefore, the graph showing a straight line with a negative slope represents a body moving with uniform retardation.
A horizontal line shows uniform velocity, a rising straight line shows uniform acceleration, and a curved line shows non-uniform acceleration. Only the straight line sloping downward is correct.
Answer:The velocity-time graph that is a straight line sloping downward represents uniform retardation. In the diagram above, this is option C.
