The figure shows an arrangement in which four disks are suspended by cords. The longer, top cord loops over a frictionless pulley and pulls with a force of magnitude 93.4 N on the wall to which it is attached. The tensions in the shorter cords are T1 = 61.4 N, T2 = 41.5 N, and T3 = 7.9 N. What are the masses of (a) disk A, (b) disk B, (c) disk C, and (d) disk D?

Can't help without the picture, but to me it seems like all you have to do is divide each tension force by g.

To find the masses of the disks, we can use Newton's second law and analyze the forces acting on each disk.

Let's assign the following variables:
m_A: mass of disk A
m_B: mass of disk B
m_C: mass of disk C
m_D: mass of disk D

We can start by analyzing the forces acting on disk A:

1. T1: The tension in the cord connected to disk A. This tension is directed upwards.
2. m_A * g: The weight of disk A. This weight is directed downwards.
3. F_t: The force applied to the wall due to the longer top cord. It is directed to the left.

Using Newton's second law, we can write the equation for disk A:

T1 - m_A * g = 0 (Equation 1)
F_t = m_A * a (Equation 2)

Note that the acceleration of the system is a, and it is the same for all disks since they are connected by inextensible cords.

Moving on to disk B:

1. T2: The tension in the cord connected to disk B. This tension is directed upwards.
2. m_B * g: The weight of disk B. This weight is directed downwards.
3. m_B * a: The force due to the acceleration of the system, acting to the right.

For disk B, we can write the equation:

T2 - m_B * g = m_B * a (Equation 3)

Now, let's consider disk C:

1. T3: The tension in the cord connected to disk C. This tension is directed upwards.
2. m_C * g: The weight of disk C. This weight is directed downwards.
3. m_C * a: The force due to the acceleration of the system, acting to the right.

For disk C, we can write the equation:

T3 - m_C * g = m_C * a (Equation 4)

Finally, let's analyze disk D:

1. m_D * g: The weight of disk D. This weight is directed downwards.
2. m_D * a: The force due to the acceleration of the system, acting to the right.

For disk D, we can write the equation:

m_D * g = m_D * a (Equation 5)

To solve these equations, we can use the given values:

T1 = 61.4 N
T2 = 41.5 N
T3 = 7.9 N
F_t = 93.4 N

We also know that the acceleration of the system, a, can be determined as:

a = F_t / (m_A + m_B + m_C + m_D)

Let's substitute these values into the respective equations and solve them step-by-step.

To solve this problem, we will use the concepts of Newton's laws of motion and the relationship between force, mass, and acceleration.

First, let's analyze the forces acting on each disk:

(a) Disk A:
There are two forces acting on Disk A: the tension in the shorter cord T1 and the weight (gravitational force) acting downward. We can write the equation as follows:
T1 - mg = 0, where m is the mass of Disk A.

(b) Disk B:
For Disk B, there are three forces acting: T1, the tension in the longer cord (equal to the force pulling on the wall), and the weight. Therefore:
T1 + T2 - mg = 0, where m is the mass of Disk B.

(c) Disk C:
For Disk C, there are three forces acting: T2, the tension in the longer cord, and the weight. Thus:
T2 + T3 - mg = 0, where m is the mass of Disk C.

(d) Disk D:
For Disk D, there is only the tension force T3 and the weight acting downward:
T3 - mg = 0, where m is the mass of Disk D.

To find the mass of each disk, we need to solve these four equations simultaneously.

From these equations, we can see that the mass of each disk can be calculated using the following formulas:

(a) For Disk A: m = T1 / g, where g is the acceleration due to gravity (approximately 9.8 m/s^2).
(b) For Disk B: m = (T1 + T2) / g
(c) For Disk C: m = (T2 + T3) / g
(d) For Disk D: m = T3 / g

Now, we can substitute the given tension values to find the masses:

(a) Disk A: m = 61.4 N / 9.8 m/s^2 = 6.27 kg (rounded to two decimal places)
(b) Disk B: m = (61.4 N + 41.5 N) / 9.8 m/s^2 = 10.89 kg (rounded to two decimal places)
(c) Disk C: m = (41.5 N + 7.9 N) / 9.8 m/s^2 = 4.91 kg (rounded to two decimal places)
(d) Disk D: m = 7.9 N / 9.8 m/s^2 = 0.81 kg (rounded to two decimal places)

Therefore, the masses of the disks are:
(a) Disk A: 6.27 kg
(b) Disk B: 10.89 kg
(c) Disk C: 4.91 kg
(d) Disk D: 0.81 kg