The previous post about kinematics deals with SPEED AND VELOCITY and it can be browsed here.
Acceleration as the rate of change of velocity with time.
The average acceleration `a over a time interval is defined as the change of velocity divided by the time interval :
`a = D v /Dt .
where v2 and v1 are the instantaneous velocities or simply velocities at time t2 and t1. It is the average change of velocity per unit time. The SI unit of acceleration is m s–2 .
On a plot of velocity versus time, the average acceleration is the slope of the straight line connecting the points corresponding to (v2, t2) and (v1, t1). The average acceleration for velocity-time graph shown in figure for different time intervals 0 s - 10 s, 10 s – 18 s, and 18 s and – 20 s are :
0 s - 10 s `a = 24 - 0 /10 - 0 = 2.4 m s–2 .
10 s - 18 s `a = 24 - 24 / 18 - 10 = 0 m s–2 .
18 s - 20 s `a = 0 - 24 / 20 - 18 = -12 m s–2.
Instantaneous acceleration is defined as rate of change of velocity at any particular instant.It is shown as a = dv/dt .The acceleration at an instant is the slope of the tangent to the v–t curve at that instant.
Since velocity is a quantity having both magnitude and direction, a change in velocity may involve either or both of these factors. Acceleration, therefore, may result from a change in speed (magnitude), a change in direction or changes in both. Like velocity, acceleration can also be positive, negative or zero.
Position-time graphs for motion with positive, negative and zero acceleration are shown in figures (a), (b) and (c), respectively.
The graph curves upward for positive acceleration; downward for negative acceleration and it is a straight line for zero acceleration.
The area under the curve represents the displacement over a given time interval.of velocity-time graph for any moving object .
Let us check for a simple case as follows.
Let an object moving with constant velocity u. Its velocity-time graph is as shown in figure.
The v-t curve is a straight line parallel to the time axis and the area under it between t = 0 and t = T is the area of the rectangle of height u and base T. Therefore, area = u × T = uT which is the displacement in this time interval.
47.45
RELATED POSTS
One dimensional motion
Speed and Velocity
Acceleration as the rate of change of velocity with time.
The average acceleration `a over a time interval is defined as the change of velocity divided by the time interval :
`a = D v /Dt .
where v2 and v1 are the instantaneous velocities or simply velocities at time t2 and t1. It is the average change of velocity per unit time. The SI unit of acceleration is m s–2 .
On a plot of velocity versus time, the average acceleration is the slope of the straight line connecting the points corresponding to (v2, t2) and (v1, t1). The average acceleration for velocity-time graph shown in figure for different time intervals 0 s - 10 s, 10 s – 18 s, and 18 s and – 20 s are :
0 s - 10 s `a = 24 - 0 /10 - 0 = 2.4 m s–2 .
10 s - 18 s `a = 24 - 24 / 18 - 10 = 0 m s–2 .
18 s - 20 s `a = 0 - 24 / 20 - 18 = -12 m s–2.
Instantaneous acceleration is defined as rate of change of velocity at any particular instant.It is shown as a = dv/dt .The acceleration at an instant is the slope of the tangent to the v–t curve at that instant.Since velocity is a quantity having both magnitude and direction, a change in velocity may involve either or both of these factors. Acceleration, therefore, may result from a change in speed (magnitude), a change in direction or changes in both. Like velocity, acceleration can also be positive, negative or zero.
Position-time graphs for motion with positive, negative and zero acceleration are shown in figures (a), (b) and (c), respectively.
The graph curves upward for positive acceleration; downward for negative acceleration and it is a straight line for zero acceleration.The area under the curve represents the displacement over a given time interval.of velocity-time graph for any moving object .
Let us check for a simple case as follows.
Let an object moving with constant velocity u. Its velocity-time graph is as shown in figure.
The v-t curve is a straight line parallel to the time axis and the area under it between t = 0 and t = T is the area of the rectangle of height u and base T. Therefore, area = u × T = uT which is the displacement in this time interval.47.45
RELATED POSTS
One dimensional motion
Speed and Velocity
PN Junction Diode in Forward Bias and Reverse Bias
Solving Problems on the Concept of P N Junction Diode
Solving Problems on the Concept of P N Junction Diode
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