Question

6. A 2.0-kg object moves in a straight line on a horizontal frictionless surface. The graph above shows the velocity of the object as a function of time. The various equal time intervals (sections) are labeled using Roman numerals: I, II, III, IV, and V. The net force on the object always acts along the line of motion of the object Which section(s) of the graph correspond to a condition of zero net force? a. b. Which section(s) of the graph corresponds to the application of the largest c. In which section(s) of the graph is the magnitude of the net force decreasing? d. In which section(s) of the graph is the net force changing? Time (s)

Answer 1

part (a) - condition of net force zero is that the momentum of the particle to be constant

We know that momentum P =MV

M is constant.if V constant then P also constant

We clearly see in the graph section (2),section(4) velocity of the particle is constant. In these two section net force is zero.

part (b) we know that if a constant net force is acting on a particle then velocity increase linearly with respect to time .so in the graph section(3) has constant net force.

Part (c) When a decreasing net force acting on a particle then retardation take place and velocity of the particle will decrease with respect to time so in the graph section(5) has decreasing net force.

Part (d) When a changing net force acting on a particle then velocity time graph of the particle nonlinear increasing or decreasing graph so in the given graph section (1) and section (5) has changing net force.