A string (A) hanging from the ceiling has a 1 kg mass attached to it and hanging below this mass is string (B) with a 2 kg mass attached. Both of the strings are massless.
How do I calculate the tension in Cord B?
Schematically, it looks like this (turned 90 degrees)
Ceiling|-->-A-<---1kg--->-B-<----2kg
The only mass string B is supporting is the 2kg mass. So the tension in string B is
Tension
=mg
=2kg * g
=2*9.8 N
=19.6 N.
To calculate the tension in Cord B, you can consider the forces acting on the system. In this case, there are two masses involved: 1 kg and 2 kg. Let's label the tension in Cord A as T_A and the tension in Cord B as T_B.
First, let's consider the 1 kg mass. The tension in Cord A, T_A, supports the weight of this mass (mg). So we have:
T_A = 1 kg * 9.8 m/s^2 (where g is the acceleration due to gravity)
Next, let's focus on the 2 kg mass. The total tension at the bottom of Cord B is the sum of T_A and T_B. This total tension must be equal to the weight of the 2 kg mass (2 kg * g):
T_A + T_B = 2 kg * 9.8 m/s^2
Now, substitute the value of T_A from the previous equation:
1 kg * 9.8 m/s^2 + T_B = 2 kg * 9.8 m/s^2
Simplifying the equation:
9.8 N + T_B = 19.6 N
Finally, subtracting 9.8 N from both sides of the equation, we find:
T_B = 19.6 N - 9.8 N
So, the tension in Cord B is 9.8 N.