At t = 0 a block with mass m = 5 kg moves with a velocity v = 2 m/s at position xo = -.33 m from the equilibrium position of the spring. the block is attached to a massless spring of spring constant k = 61.2 n/m and slides on a frictionless surface. at what time will the block next pass x = 0, the place where the spring is unstretched? t1 =

When an object is heated it contracts. a. true b. false

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

You have two photos of a person walking. one shows the person at the corner of third and main streets, the other shows the person at the corner of tenth and main streets. there are lampposts at every corner in this town, and the first picture shows it to be 10: 32: 00 exactly. the second picture shows it to be 10: 49: 30. you know three facts: (1) all of the clocks are synchronized; (2) there are exactly 12 equal-sized blocks per kilometer in this town; and (3) the streets that cross main in this area are numbered consecutively, with no interruptions. what is the person’s average speed in kilometers per hour?