h11_6a

# h11_6a - Problem 7.2 In the rough area the block...

This preview shows pages 1–2. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Problem 7.2 In the rough area, the block decelerates and travels a distance s. We can use the equation v f 2 = v i 2 +2a Δ x. When Δ x =s, v f =0. We can solve for acceleration: a=-v i 2 /2s. We want to find the distance traveled when v f = v i /3. Using v f 2 = v i 2 +2a Δ x, we get Δ x=8s/9 Problem 7.5 We could answer this problem using forces and the equations you learned at the beginning of the class about velocity and acceleration. You might say that since a=gsin θ , the mass on plane 2 has higher velocity at the bottom. However, the θ =25 block travels a greater distance to the bottom and has more time to accelerate. Using conservation of energy, mgh=.5mv 2 . Since they start at the same height and the masses are the same, the velocity is the same. Problem 7.6 From conservation of energy, U grav =K+W friction . Energy is dissipated through air friction so W friction >0 and K< U grav Problem 7.8 They have different initial gravitational energies since the masses are different.They have different initial gravitational energies since the masses are different....
View Full Document

## This note was uploaded on 12/09/2009 for the course PHYS PHYS 6a taught by Professor Geller during the Spring '09 term at UCSB.

### Page1 / 4

h11_6a - Problem 7.2 In the rough area the block...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online