4. A 62.0-kg person, standing on the diving board, dives straight down into the water. Just before striking the water, her speed is 5.50 m/s. At a time of 1.65 s after she enters the water, her speed is reduced to 1.10 m/s. What is the net average force (magnitude and direction) that acts on her when she is in the water?

Respuesta :

To solve this problem it is necessary to apply the concepts related to the Moment. The moment in terms of the Force and the time can be expressed as

[tex]\Delta P = F\Delta t[/tex]

F = Force

[tex]\Delta t = Time[/tex]

At the same time the moment can be expressed in terms of mass and velocity, mathematically it can be given as

[tex]P = m \Delta v[/tex]

Where

m = Mass

[tex]\Delta v =[/tex] Change in velocity

Our values are given as

[tex]\Delta t=1.65s[/tex]

By equating the two equations we can find the Force,

[tex]F\Delta t = m\Delta v[/tex]

[tex]F = \frac{m\Delta v}{\Delta t}[/tex]

[tex]F = \frac{62(1.1-5.5)}{1.65}[/tex]

Therefore, the net average force will be:

[tex]F = - 165N[/tex]

The negative symbol indicates that the direction of the force is upwards.

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