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Renni202
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I hope I am posting in the right place. I am a 1st year University student. Although I am undertaking a BSc in Computer and Electronic System Engineering I have a Mechanical Principles module which I am finding a little bit of a struggle.
Mechanical Principles - Dynamics:
a) A diaphragm type gas compressor of mass 235 kg is supported by 4 springs which are arranged in parallel. The springs each have stiffnesses of 40 kN/m, 40 kN/m, 45 kN/m and 45 kN/m respectively. Determine:
i) the total stiffness of the spring system in N/m;
ii) the natural frequency of free vibration of the machine in Hz;
iii) the time elapsed after 5 cycles of free vibration, and show this on an amplitude-time graph.Answer
i) KT = 2K1+2K2
KT=170x103 N/m
i.e KT=170 kN/m
(It askes for the answer in N/m so should I still take it to kN/m or stop at N/m?)
ii) fn=1/2πK/m=ωn/2π
=1/2π√170x103/235
=4.2 Hz
iii) T=1/fn=1/4.2=0.24s for 1 cycle 1.2 for 5 cycles
I am looking for confirmation that I am on the right track with my answers and any guidance offered on making an amplitude-time graph. It really is much appreciated.
Mechanical Principles - Dynamics:
a) A diaphragm type gas compressor of mass 235 kg is supported by 4 springs which are arranged in parallel. The springs each have stiffnesses of 40 kN/m, 40 kN/m, 45 kN/m and 45 kN/m respectively. Determine:
i) the total stiffness of the spring system in N/m;
ii) the natural frequency of free vibration of the machine in Hz;
iii) the time elapsed after 5 cycles of free vibration, and show this on an amplitude-time graph.Answer
i) KT = 2K1+2K2
KT=170x103 N/m
i.e KT=170 kN/m
(It askes for the answer in N/m so should I still take it to kN/m or stop at N/m?)
ii) fn=1/2πK/m=ωn/2π
=1/2π√170x103/235
=4.2 Hz
iii) T=1/fn=1/4.2=0.24s for 1 cycle 1.2 for 5 cycles
I am looking for confirmation that I am on the right track with my answers and any guidance offered on making an amplitude-time graph. It really is much appreciated.