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3 years ago

11

A 6.9 kg object is suspended by a string from the ceiling of an elevator. The acceleration of gravity is 9.8 m/s 2 . Determine t

he tension in the string if it is accelerating upward at a rate of 2.9 m/s 2 . Answer in units of N.

1 answer:

lina2011 [118]3 years ago

6 0

Answer:

Tension, T = 87.63 N

Explanation:

Given that,

Mass of the object, m = 6.9 kg

The string is acting in the upward direction, a = 2.9 m/s²

Acceleration due to gravity, g = 9.8 m/s²

As the lift is accelerating upwards, it means the net force acting on it is given by :

T = m(a+g)

= 6.9 (2.9+9.8)

= 6.9(2.7)

= 87.63 N

So, the tension in the string is 87.63 N.

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