need help on problem 4.9, the second part for question b...show that the total potential energy has the form1/2k y^2....

You are driving to the grocery store at 22 {\rm m}/{\rm s}. You are 110 {\rm m} from an intersection when the traffic light turns red. Assume that your reaction time is 0.78 {\rm s} and that your car brakes with constant acceleration. How far are you from the intersection when you begin to apply...

A 457 N net force causes a 148 m/s2 acceleration. Determine the object's mass

As you will see in experiment 9, a string connecting a cart and a hanger goes over a pulley, as in the sketch below on the left. They pulley has tensions T1 and T2 acting upon it, as shown below in the center.Assume no slip between the string and the pulley throughout this problem. 1. What is...

A 1500 {\rm kg} car skids to a halt on a wet road where mu_k = 0.55.

If the stretch of a spring is doubled, the force it exerts is also doubled. By what factor does the spring's potential energy increase?

when combing your hair you scuff electrons from your hair onto the comb?

Sam, whose mass is 85 kg, takes off across level snow in his jet powered skis. The skis have a thrust of 189 N and a coefficient of kinetic friction on snow of 0.1. Unfortunately, the skis run out of fuel after only 8 s.

Sam, whose mass is 85 kg, takes off accross level snow in his jet powered skis. The skis have a thrust of 189 N and a coefficient of kinetic friction on snow of 0.1. Unfortunatately, the skis run out of fuel after only 8 s.

A child slides down a slide with a 25 incline, and at the bottom her speed is precisely two-thirds what it would have been if the slide had been frictionless. Calculate the coefficient of kinetic friction between the slide and the child.