On a frictionless horizontal air table, puck A (with mass 0.255 kg ) is moving toward puck B (with mass 0.375 kg ), which is initially at rest. After the collision, puck A has velocity 0.117 m/s to the left, and puck B has velocity 0.650 m/s to the right.

What was the speed vAi of puck A before the collision?

Calculate ΔK, the change in the total kinetic energy of the system that occurs during the collision.

2)

A 25.0 mL sample of 0.160 M KOH is titrated with 0.250 M HCl.

Determine the following quantities:

a)

The initial pH of the KOH solution before any acid is added.

b)

The pH of the solution after 3.00 mL of HCl is added.

c)

The quantity of HCl solution required to reach the equivalence

point.

d)

The pH of the solution at the equivalence point.

e)

The pH of the solution after20.0 mL of HCl is added.

Carefully reflect on what it means to be ‘informed’ as you make decisions and judgments.

In addition, what is your perspective on the role of, or need for, authorities in terms of making good decisions (before and after our reading)?

For example, if there are medical concerns, you would consult with a doctor.

If there are concerns over the environment, you would consult with an environmental scientist or other expert in the field.What about morality?

What about becoming the kind of person you want to be?

A very wide embankment with height of 3m and the soil unit weight 19 kn/m3 to be constructed. Calculate the normal stress, water pressure and effective stress at two positions: At the middle of clay, the depth = 5 m and the saturated unit weight = 27 kn/m3, and at the middle of sand, the depth = 5 and the saturated unit weight = 21 kn/m3.

For two cases

- Before constructing embankment

-Instantly after constructing the embankment

A government wishes to borrow £1 million. It issues a one-year bond at a price of £950,000 at a fixed rate of interest of 5%. Suppose in investors become concerned about a possible default, causing the bond price to fall to £930,000.

1. Calculate the bond yield before and after the fall in the bond price.
2. How will this affect the interest rates that companies and households pay on their debts?
3. What can governments do to prevent a debt default?

Two 2.3 kg bodies, A and B, collide. The velocities before the collision are v → A = ( 34 i ̂ + 29 j ̂ ) m/s and v → B = ( 19 i ̂ + 1.6 j ̂ ) m/s . After the collision, v → A ′ = ( 4.0 i ̂ + 12 j ̂ ) m/s . What are (a) the x-component and (b) the y-component of the final velocity of B? (c) What is the change in the total kinetic energy (including sign)?

After leaving the end of a ski ramp, a ski jumper lands downhill at a point that is displaced 50.0 m horizontally from the end of the ramp. His velocity, just before landing, is 24.0 m/s and points in a direction 34.1 ° below the horizontal. Neglecting air resistance and any lift that he experiences while airborne, find (a) the magnitude and (b) the direction of his initial velocity when he left the end of the ramp.