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1 year ago

6

In a study conducted by a University of Illinois researcher, the football team at Unity High School in Tolono, IL was equipped f

or an entire season with helmets containing accelerometers. Information about every impact in practice and in games was sent to a computer present on the sidelines. The study found that the average force on a top of the head impact was 1770 N. If the initial velocity of the head was 2.09 m/s and the collision brings the head to a stop, and assuming the head has a mass of 4.12 kg, determine the duration of the impact.
(Note: we are treating the head as a free body which is a bit of an approximation).

1 answer:

Angelina_Jolie [31]1 year ago

6 0

The duration (i.e time) of the impact, given that the head impact was 1770 N is 0.005 s

<h3>How do I determine the duration (i.e time)?</h3>

Impulse is defined as the change in momentum of an object. It is expressed as:

Impulse = change in momentum

Impulse = final momentum – Initial momentum

Impule = m(v - u)

Impulse = force × time

Impulse = Ft

Thus,

Ft = m(v - u)

Where

F is the force
t is the time
m is the mass
u is the initial velocity
v is the final velocity

Now, we can obtain the duration (i.e time) of the impact. Details below:

Force (F) = 1770 N
Initial velocity = 2.09 m/s
Mass (m) = 4.12 Kg
Final velocity = 0 m/s
Duration (t) =?

Ft = m(v + u) since the collision came to a stop

1770 × t = 4.12 × (0 + 2.09)

1770 × t = 4.12 × 2.09

Divide both sides by 1770

t = (4.12 × 2.09) / 1770

t = 0.005 s

Thus, the duration is 0.005 s

Learn more about time:

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The given question is incomplete. The complete question is as follows.

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3 years ago

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