Given that the tension T1=20N calculate the tension T2 and the mass of the hanging object. The angles of the strings with the ceiling are 25 degrees and 40 degrees respectively.

To find the tension T2 and the mass of the hanging object, we can use the principles of equilibrium for forces acting on the object.

First, let's label the angles of the strings:
- Angle between T1 and the horizontal is 25 degrees.
- Angle between T2 and the horizontal is 40 degrees.

Now, let's break down the tension forces into horizontal and vertical components.

For T1:
- The horizontal component of T1, T1h, is given by T1h = T1 * cos(angle).
- The vertical component of T1, T1v, is given by T1v = T1 * sin(angle).

For T2:
- The horizontal component of T2, T2h, is given by T2h = T2 * cos(angle).
- The vertical component of T2, T2v, is given by T2v = T2 * sin(angle).

Since the system is in equilibrium, the sum of the vertical components of the tensions should equal the weight of the hanging object.

Now, let's solve for T2 and the mass of the hanging object using the information given:

Step 1: Calculate the vertical component of T1:
T1v = T1 * sin(25 degrees).
T1v = 20 N * sin(25 degrees).
T1v ≈ 8.57 N.

Step 2: Calculate the vertical component of T2:
T2v = T2 * sin(40 degrees).

Step 3: Set up an equation for the vertical equilibrium:
T1v + T2v = m * g,
where m is the mass of the hanging object and g is the acceleration due to gravity (approximately 9.8 m/s^2).

Step 4: Use the equation from step 3 to solve for T2:
T2v = m * g - T1v.

Step 5: Substitute the values into the equation:
T2 * sin(40 degrees) = m * 9.8 m/s^2 - 8.57 N.

Step 6: Solve for T2:
T2 ≈ (m * 9.8 m/s^2 - 8.57 N) / sin(40 degrees).

Step 7: Once you have the value of T2, you can substitute it into one of the equations used to solve for the mass. For example, you can use the horizontal component of T2:
T2h = T2 * cos(40 degrees) = mg * cos(40 degrees).
And solve for the mass m.

Note: Make sure that all angles are in radians when using trigonometric functions in calculations.