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3 years ago

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A 60-kg passenger is in an elevator which is initially at rest. The elevator starts to travel downward. It reaches a downward sp

eed of 7m/sec in a time of 4 seconds

1 answer:

Delvig [45]3 years ago

4 0

Answer:

a. Acceleration = 1.75 m/s²

b. Force = 105 Newton.

Explanation:

<u>Given the following data:</u>

Mass = 60kg

Final velocity = 7m/s

Time = 4 seconds

Required to find the acceleration and force of the body;

a. To find the acceleration;

Mathematically, acceleration is given by the equation;

$Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}$

Where;

a is acceleration measured in $ms^{-2}$
v and u is final and initial velocity respectively, measured in $ms^{-1}$
t is time measured in seconds.

Since the elevator is starting from rest, its initial velocity is equal to 0m/s.

Substituting into the equation, we have;

$Acceleration = \frac{7 - 0}{4}$

$Acceleration = \frac{7}{4}$

<em>Acceleration = 1.75 m/s²</em>

b. To find the force;

$Force = mass * acceleration$

Substituting into the equation, we have;

$Force = 60 * 1.75$

<em>Force = 105 Newton. </em>

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