# What is the distance from the mass to the circle?

A block of mass 0.5 kg is pushed against a horizontal spring of negligible mass, compressing

the spring a distance of ∆x as shown in the figure. The spring constant is 467 N/m. When

released, the block travels along a frictionless,

horizontal surface to point B, the bottom of

a vertical circular track of radius 0.7 m, and

continues to move up the track. The speed

of the block at the bottom of the track is

16 m/s, and the block experiences an average frictional force of 6 N while sliding up the

track.

The acceleration of gravity is 9.8 m/s 2.

What is ∆x?

Answer in units of m.

Please give an explanation!

What is the speed of the block at the top of

the track?

### 1 Answer

- NCSLv 78 months agoFavourite answer
Most of the data is irrelevant as far as the question goes.

Spring energy becomes kinetic energy:

½kx² = ½mv²

½ cancels

467N/m * x² = 0.5kg * (16m/s)²

solves to

x = 0.52 m