# Physics

posted by .

I THINK SOMEONE HAS THIS SAME QUETION! A massless spring of constant k = 91.0 N/m is fixed on the left side of a level track. A block of mass m = 0.50 kg is pressed against the spring and compresses it a distance of d. The block (initially at rest) is then released and travels toward a circular loop-the-loop of radius R = 1.5 m. The entire track and the loop-the-loop are frictionless, except for the section of track between points A and B. Given that the coefficient of kinetic friction between the block and the track along AB is µk = 0.24, and that the length of AB is 2.5 m, determine the minimum compression d of the spring that enables the block to just make it through the loop-the-loop at point C. [Hint: The force of the track on the block will be zero if the block barely makes it through the-loop-the-loop.]

• Physics -

Assuming point C is at the top, then

g= v^2/r so you have to calculate v at the top.

So energy at the bottom must equal KE at the top + the change in PE to get to the top

RequiredKEbotom= 1/2 m*vtop^2+mg(2r)

Now, you have losses before you get there due to friction, mu*mg*2.5, so that has to be added to get the initial KE at the spring.

PEspring= mu*mg*2.5+1/2m vtop^2+mg(2r)

PE spring= 1/2 k d^2, solve for d.

• Physics -

thank you, but i am exteremly confused! so i just use PE spring to find d?

• Physics -

i guess i'm just confused on the mu means static friction? .24?

• Physics -

is mu friction? .24?

• Physics -

Blah

## Similar Questions

1. ### Physics

A massless spring of constant k = 88.9 N/m is fixed on the left side of a level track. A block of mass m = 0.50 kg is pressed against the spring and compresses it a distance of d. The block (initially at rest) is then released and …
2. ### Physics

A massless spring of constant k = 91.0 N/m is fixed on the left side of a level track. A block of mass m = 0.50 kg is pressed against the spring and compresses it a distance of d. The block (initially at rest) is then released and …
3. ### Physics URGENT!!!

A massless spring of constant k =84.8 N/m is fixed on the left side of a level track. A block of mass m = 0.5 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) is …
4. ### Physics URGENT!!!

: A massless spring of constant k =84.8 N/m is fixed on the left side of a level track. A block of mass m = 0.5 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) …

A massless spring of constant k =84.8 N/m is fixed on the left side of a level track. A block of mass m = 0.5 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) is …
6. ### physics

A massless spring of constant k =60.9 N/m is fixed on the left side of a level track. A block of mass m = 0.7 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) is …
7. ### PHYSICS

A frictionless horizontal air track has a spring at either end. The spring on the left has a spring constant of 1600 N/m; the one on the right has a spring constant of 1060 N/m. A glider with a mass of 2.9 kg is pressed against the …
8. ### mechanics

Jayden holds a 3kg block pressed up against a spring on a horizontal and frictionless surface. The spring has a spring constant of 300Nm. The spring is fixed in place, but the block is free to move. The spring is initially compressed …
9. ### physics

a wooden block of mass equal to 15kg is pressed against a spring. The spring has constant of 225N/m. If the spring is compressed 0.15m, how fast will the block travel when released?
10. ### Physics

Two identical massless springs of constant k = 200N/m are fixed at opposite ends of a level track, as shown. A 5 kg block is pressed against the left spring, compressing it by 0.15m. The block is then released from rest. The entire …

More Similar Questions