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A 66-kg fellow stands on a digital scale in an elevator that accelerates upwards from rest to 4.5 m/s in 2.00 s. show answer Incorrect Answer Calculate the scale reading, in newtons, during this process (The scale exerts an upward force on him equal to its reading.)

User OdieO
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1 Answer

4 votes

Answer:

Step-by-step explanation:

mass of the fellow ( m ) = 66kg

acceleration of fellow a

v = u + at

4.5 = 0 + a x 2

a = 4.5 /2

= 2.25 m / s²

Net force acting on fellow in upward direction by the surface of elevator

R - mg where R is reaction force of the surface of the elevator

Applying Newton's law of motion

R - mg = ma

R = m (g +a )

= 66 x ( 9.8 + 2 )

= 778.8 N

This will be the scale reading .

User BerticusMaximus
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