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Question
Figure (a) shows the displacement-time graph for the motion of a body. Use it to calculate the velocity of the body at t = 1 s, 2 s and 3 s, and then draw the velocity-time graph in Figure (b) for it.
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| (a) | (b) |
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Solution
We observe from the given displacement time graph above, that the slope is a straight line inclined with time axis, so the body is moving with uniform velocity.
velocity = Slope of straight line
t = 1; velocity = `2/1` = 2 m/s
t = 2; velocity = `4/2` = 2 m/s
t = 3; velocity = `6/3` = 2 m/s
Hence, velocity at t = 1 s, 2 s and 3 s is equal to 2 m s-1
Velocity-time graph for the motion of a body is given below:
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The graph given in figure is true for
Assertion: The position-time graph of a uniform motion in one dimension of a body can have a negative slope
Reason: When the speed of the body decreases with time then, the position-time graph of the moving body has a negative slope.
