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wariber [46]
2 years ago
10

3) A 30 kg child slides freely across a "Slip and Slide" on LEVEL GROUND. While the child slides, the force applied to keep them

sliding is 0 N. The coefficient of kinetic friction is 0.02. What is the acceleration experienced by the child?
Physics
1 answer:
zavuch27 [327]2 years ago
4 0

Answer:

a = 0.1962 m/s^2

Explanation:

The magnitude of kinetic friction exerted is given by

F_k=\mu_kN

Where, μ_k= coefficient of kinetic friction= 0.02 and N = reaction force = mg

Where m= mass = 30 Kg and, g is acceleration due to gravity =9.81 m/s^2

F_k=0.02×30×9.81 =5.886 N

Now, since, there is no applied force this kinetic friction force will cause acceleration of the child

⇒ ma = F_k

here, a is the acceleration

⇒30a = 5.886

⇒ a = 0.1962 m/s^2

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When solving question that contains equations and the use mathematical computations, It is always ideal to list the parameters given.

Now, given that:

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Assumptions:

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∴

For a motion under constant acceleration, we can apply the kinematic equation:

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From the above equation, making acceleration (a) the subject of the formula:

\mathsf{v^2 - u^2 =2as }

\mathsf{a = \dfrac{v^2 - u^2 }{2s}}

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a = - 385.86 m/s²

Similarly, from the kinematic equation of motion, the formula showing the relation between time, acceleration and velocity is;

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\mathsf{t = \dfrac{-u}{a}}

\mathsf{t = \dfrac{-27.78}{-385.86}}

t = 0.07 seconds

An airbag is designed in such a way as to prevent the driver from hitting on the steering wheel or other hard substance that could damage the part of the body. The use of the seat belt is to keep the driver in shape and in a balanced position against the expansion that occurred by the airbag during the collision on the brick wall.

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3 0
3 years ago
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Answer:

E(final)/E(initial)=2

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E=\sigma/\epsilon_{o}=Q/(L^{2}*\epsilon_{o})\\

So, if the charge is doubled the Electric field is doubled too

E(final)/E(initial)=2

3 0
3 years ago
A series of pulses, each of amplitude 0.1 m, is sent down a string that is attached to a post at one end. The pulses are reflect
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With this information we analyze a point on the string where the incident pulse is and each reflected with an amplitude A = 0.1 m, the resulting is

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The minimum speed can be determined by;

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If the appropriate values of the variables are substituted into the expression, the value of the minimum speed required can be determined.

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