What is the walking speed of the student, from home to the bus stop?
Applications and Skills |
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Determining instantaneous and average values for velocity, speed |
and acceleration |
Solving problems using equations of motion for uniform |
acceleration |
Determining the acceleration of free-fall experimentally |
Sketching and interpreting motion graphs |
Analysing projectile motion, including the resolution of vertical |
and horizontal components of acceleration, velocity and |
displacement |
Qualitatively describing the effect of fluid resistance on falling |
objects or projectiles, including reaching terminal speed |
Understandings |
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Distance and displacement |
Speed and velocity |
Acceleration |
Graphs describing motion |
Equations of motion for uniform acceleration |
Projectile motion |
Fluid resistance and terminal speed |
$$ \text{Booklet:}\\ v= u+at\\ s=ut+\frac{1}{2}at^2\\ v^2 = u^2 + 2as\\s=\frac{(v+u)t}{2}\\\text{ }\\s\text{ = displacement (metres)}\\u\text{ = initial velocity (metres per second)}\\v\text{ = final velocity (metres per second)}\\a\text{ = acceleration (metres per second per second )}\\t\text{ = total time (seconds)} $$
Find each displacement. Note that the x = 0 coordinate has been placed on the number lines.
A ball starts rolling down a hill from rest with a constant acceleration of . Find the velocity of the ball after 4 seconds. How far has the ball travelled in that time?
A cyclist is in a race and 100 metres from the finish he decides to accelerate his speed. The cyclist maintains a constant acceleration of $0.4\text{m/s}^2$. If the cyclist crosses the finish line with a speed of 17m/s, how fast was he cycling when he started to accelerate?
Speed: scalar quantity defined as $\frac{\text{distance travelled on journey}}{\text{time taken for journey}}$. The unit for speed is $\bold{ms^{-1}}$.
Velocity: is a vector term and, just as for displacement , a magnitude and direction are required.
Defined as:
$$ v= \frac{\text{displacement of a journey}}{\text{time for a journey}} = \frac{\Delta x}{\Delta t}= \frac{s}{t} $$
Being the rate of change of velocity, it can also be described as the derivative of a velocity/time curve.