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Q- Application of calc to phys world. (1 Viewer)
- Thread starter imoO
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shuning
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回复: Q- Application of calc to phys world.
velocity is the 1st deriverative
acceleration is the 2nd deriverative
i can help if u post the question here
velocity is the 1st deriverative
acceleration is the 2nd deriverative
i can help if u post the question here
~caramello~
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9) its projected at 30m/s (starts off at 30m/s) and decelerates at 10m/s^2 (slows down 10m/s every second). so the equation for the velocity should be
30-10t where t is the number of seconds.
b) and to find the equation of h, it is asking for the equation of displacement.
hence u integrate the velocity (30-10t)
c) the greatest height reached would be the time when velocity = 0 (projected up, slowing down every second until it reaches 0, then acclerates back downwards). so 30-10t=0. You now get the time when it reaches max height. You just sub it in the equation for height.
d) time taken for it to reach point of projection is when displacement = 0 (when it returns to its starting position)
question 10 is very similar. hope it helps =]
30-10t where t is the number of seconds.
b) and to find the equation of h, it is asking for the equation of displacement.
hence u integrate the velocity (30-10t)
c) the greatest height reached would be the time when velocity = 0 (projected up, slowing down every second until it reaches 0, then acclerates back downwards). so 30-10t=0. You now get the time when it reaches max height. You just sub it in the equation for height.
d) time taken for it to reach point of projection is when displacement = 0 (when it returns to its starting position)
question 10 is very similar. hope it helps =]
~caramello~
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umm.. no. velocity is not constant. It starts off at a constant rate and changes every second (could be due to gravity/air resistance etc).
I'm not that gud at explaining but here goes...
ok..velocity is the speed at which something is moving. when u throw a ball up, it goes up, slows down, stops at the max height and comes back down. so during all the time the speed of the ball is changing.
acceleration is the RATE at which the speed is changing (hence dv/dt, we differentiate the velocity equation to get acceleration). It is how much the object speeds up or slows down. In this case acceleration is constant. ( rate at which the object changing speed is -10m/s)
well..hope that helps..
I'm not that gud at explaining but here goes...
ok..velocity is the speed at which something is moving. when u throw a ball up, it goes up, slows down, stops at the max height and comes back down. so during all the time the speed of the ball is changing.
acceleration is the RATE at which the speed is changing (hence dv/dt, we differentiate the velocity equation to get acceleration). It is how much the object speeds up or slows down. In this case acceleration is constant. ( rate at which the object changing speed is -10m/s)
well..hope that helps..