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Luba_88 [7]
3 years ago
5

A motorcycle rider travelling at 30m/s sees a child run into the streets 190m ahead. If the rider takes 1 second to react before

beginning to decelerate at a rate of 3m/s^2, does he stop in time, and if so by what distance is the child safe? (Hint: there a 2 stages of motion)
Physics
1 answer:
adell [148]3 years ago
5 0

Answer:

The distance by which the child is safe is  k  =  10 \  m

Explanation:

From the question we are told that

  The speed of the motorcycle is  v_n  =  30 m/s

   The distance of the child from the motorcycle is L =  190 m

    The reaction time is  t_r  =  1 \  s

    deceleration is  a =  -3m/s^2

Generally the distance covered during the reaction time is  

    D =  v_n  *  t_r

=>D =  30  * 1

=> D =  30 \  m

Generally the distance covered during the deceleration

     v^2 =  u^2 + 2as

Here v is the final velocity which is  zero  

So

   0 =  30 ^2 + 2 * (-3)s

=> s =  150 \  m

So the total distance the motorcycle rider will cover before coming to rest is  

     d  =  D +  s

=>   d =  30 + 150

=>  d =  180 \  m

Therefore the amount of distance by which the child id safe is  

    k  =  L -d

=> k =  190 -180

=>  k  =  10 \  m

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Answer:

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Explanation:

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6 0
3 years ago
3 Draw energy transfer diagrams
timofeeve [1]

Answer:

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Please find attached the drawings of the energy transfer created with MS Visio

Explanation:

The energy transfer diagrams are diagrams that can be used to indicate the part of a system where energy is stored and the form and location to which the energy is transferred

a) The energy transfer diagram for the winding up a clockwork car is given as follows;

Mechanical kinetic energy is used to wind up (turn) the clockwork car such that the kinetic energy is transformed into potential energy and stored in the wound up clockwork as follows;

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6 0
3 years ago
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