Graphs

x-t graphs(Slope of x-t graph gives velocity)

a) for Rest

Position of Object Remains Same

x= constant

v=0

a=0

b) For Constant velocity(Positive)

Position of Object changes uniformly with time.

v=constant and +ve

a=0

v=u+at

v=u+0t

v=u

x=ut + ½ at²

x=ut +0

x=ut

value of u is +ve so slope of graph is +ve

c) For Constant velocity(Negative)

v=constant and -ve

a=0

v=u+at

v=u+0t

v=u

x=ut + ½ at²

x=ut +0

x=ut               

value of u is negative so slope of graph is negative

d) For Uniformly Accelerated Motion(negative)

Velocity decreases

a=  -ve

v=u+at

x=ut + ½ at²

x α t²

so graph is parabolic and slope also decreases with time

e) For Uniformly Accelerated Motion(+ve)

Velocity increases

a=+ve

v=u+at

x=ut + ½ at²

x α t²

so graph is parabolic and slope increases

Velocity-Time Graphs(Slope of v-t graph gives acceleration)

a) For Constant Velocity

a=0

Slope is also zero

b) For Constant Positive Acceleration

u=0

a=+ve

v=u+ at

v= at

If u is not equal to zero

u= -ve

u=+ve

c) For negative Constant Acceleration

v= u+at

u ≠ 0

as a is negative so slope is also negative