Read and analyze each word problem and give what is/are required. Write the detailed solution If possible, express your final answer in the form u(t)= Rcos(@,t – 8). 4. A 10-kg mass is attached to a...

You can use methods such as variation of parameters, application of exponential shift theorem, and evaluation of some inverse differential operators.

Extracted text: Read and analyze each word problem and give what is/are required. Write the detailed solution If possible, express your final answer in the form u(t)= Rcos(@,t – 8). 4. A 10-kg mass is attached to a spring having a spring constant of 140 N/m. The mass is started in motion from the equilibrium position with an initial velocity of 1 m/sec in the upward direction and with an applied external force F(f) = 5 sin t. Find the subsequent motion of the mass if the force due to air resistance is -90ù N.