A spring gets stretched by 8 in. if an object weighing16 Ib is attached to it. This object is pulled 4 in. below its equilibrium position and released. If the system is undamped and subjected to an external force F(t)=2 cos t, determine the displacement of the object. cos (4/3t) + cos t ] 5. 35 [y(t) = 141

si 9. A 1.65 kg box rests on a plank that is inclined at an angle of 68.0° above the horizontal. The upper end of the box is attached to a spring with a force constant of 18.0 N/m, as shown in the figure. If the coefficient of static friction between the box and the plank is 0.28, what is the maximum amount the spring can be stretched and the box remain at rest? m f60 ssf60 ssico ss$60 ssf60** ssf60 ssf60 ssf60 ssf60 ssfossf60 ssf bood ssf60 ssf60 ss ] …………¶¶¶õõ‰¶¶¶¯¯¯ ¶ 50 ssf60 s f60 ssf60 ssf60 ss£60 SS sf60160 ssf60 ssf60 ssf60ain f60 sf60 ssf60 ssf60 ssf60 ƒ60 ssf60 ssf60 ssf

You have a light spring which obeys Hooke's law. This spring stretches 2.24 cm vertically when a 2.40 kg object is suspended from it. Determine the following. (a) the force constant of the spring (in N/m) Answer____________ N/m (b) the distance (in cm) the spring stretches if you replace the 2.40 kg object with a 1.20 kg object Answer____________ cm (c) the amount of work (in J) an external agent must do to stretch the spring 8.50 cm from its unstretched position Answer____________ J

Fish are hung on a spring scale to determine their mass (most fishermen feel no obligation to report the mass truthfully). (a) What is the force constant (in N/m) of the spring in such a scale if it stretches 8.40 cm for a 14.0 kg load? | N/m (b) What is the mass (in kg) of a fish that stretches the spring 5.50 cm? |kg (c) How far apart (in mm) are the half-kilogram marks on the scale? mm