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three masses m 1 = 3.0 kg, m 2 = 9.0 kg and m 3 = 6.0 kg hang from three identic

ID: 2163808 • Letter: T

Question

three masses m1 = 3.0 kg, m2 = 9.0 kg and m3 = 6.0 kg hang from three identical springs in a motionless elevator. The springs all have the same spring constant that you just calculated above.

3) What is the distance the lower spring is stretched from its equilibrium length?

4) Now the elevator is moving downward with a velocity of v = -3.1 m/s but accelerating upward with an acceleration of a = 5.3 m/s2. (Note: an upward acceleration when the elevator is moving down means the elevator is slowing down.)

What is the force the bottom spring exerts on the bottom mass?

5) What is the distance the upper spring is extended from its unstretched length?

Explanation / Answer

Three masses m1 = 4.5 kg, m2 = 13.5 kg and m3 = 9 kg m1 = 4.5 ( 9.8 + 5 ) = 66 .6 N L spring = 100/401 * 66.6= 16.608 cm m2= 13.5 ( 9.8 + 5) = 199.8 N L spring = 100/401 * 199.8 = 49.82cm m3 = 9 ( 9.8 + 5 ) = 133.2 N L spring = 100/401 * 133.2 = 33.217 cm L spring = spring is extended from...... b c