The process of learning to place others before myself was very difficult, but very worthwhile."

Which character from this unit would be most likely to say this?

Alice

Ah Fo

Prince Harweda

Sogole

(a)

Let:

a be the acceleration of the system,

g be the acceleration due to gravity,

T be the tension in the string.

For mA:

T = mA a

For mB:

mB g - T = mB a

Adding to eliminate T:

mB g = (mA + mB) a ... (1)

a = mB g / (mA + mB)

= 7.0 * 9.81 / (11.0 + 7.0)

= 3.815 m/s^2

= 3.82 m/s^2 to 3 sig. fig.

(b)

Let:

s be the distance to the edge of the table,

t be the time taken.

s = at^2 / 2

t = sqrt (2s / a)

= sqrt (2 * 1.250 / 3.815)

= 0.810 sec to 3 sig. fig.

(c)

From (1):

(mA + mB) (a / g) = mB

mA (a / g) = mB (1 - a / g)

mA = mB (g / a - 1)

= 4.0 (100 - 1)

= 396 kg.