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2 years ago

11

A ruined in a race decides to accelerate right up to the moment he crosses the line He is the initially travelling at 5m/s and a

ccelerates at 0.4m/s² for 5 sec. find
a) the distance he covers
b) his final velocity

1 answer:

docker41 [41]2 years ago

6 0

Answer:

S = V t + 1/2 a t^2 = 5 m/s * 5 s + .2 m/s^2 * 25 s^2 =

25 m + 5 m = 30 m distance traveled

Vf = V + a t = 5 m/s + .4 m/s^2 * 5 s = (5 + 2) m/s = 7 m/s final velocity

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riadik2000 [5.3K]

Answer: $6.408(10)^{-19} C$

Explanation:

This problem can be solved by the following equation:

$\Delta K=q V$

Where:

$\Delta K=7.37(10)^{-17} J$ is the change in kinetic energy

$V=115 V$ is the electric potential difference

$q$ is the electric charge

Finding $q$ :

$q=\frac{\Delta K}{V}$

$q=\frac{7.37(10)^{-17} J}{115 V}$

Finally:

$q=6.408(10)^{-19} C$

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Vinil7 [7]

To solve this exercise, it is necessary to apply the concepts of conservation of the moment especially in objects that experience an inelastic colposition.

They are expressed as,

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Where,

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