# Previous answers scalcet7 33035mi a mass on a spring

• Homework Help
• 7
• 100% (12) 12 out of 12 people found this document helpful

This preview shows page 3 - 5 out of 7 pages.

5. 7/7 points | Previous Answers SCalcET7 3.3.035.MI. A mass on a spring vibrates horizontally on a smooth level surface (see the figure). Its equation of motion is where t is in seconds and x is in centimeters. (a) Find the velocity and acceleration at time t (b) Find the position, velocity, and acceleration of the mass at time t = 2 π / 3 = x ( t ) = 8 sin t v ( t ) = \$\$8 cos ( t ) a ( t ) = \$\$ 8 sin ( t ) x 2 π 3 . . ,
In what direction is it moving at that time? .
6. 5/5 points | Previous Answers SCalcET7 3.3.038. An object with weight W is dragged along a horizontal plane by a force acting along a rope attached to the object. If the rope makes an angle θ with the plane, then the magnitude of the force is where μ is a constant called the coefficient of friction (a) Find the rate of change of F with respect to θ F = µ W μ sin θ + cos . . θ
(b) When is this rate of change equal to 0?
(c) If W = 60 lb and μ = 0.5 , draw the graph of F as a function of Use the graph to locate the value of θ for which dF / d θ = 0. (Round your answer to two decimal places.) θ .
• • • 