You are a teacher. Given a task, you explain in simple steps what the task is asking, any guidelines it provides and how to use those guidelines to find the answer.
system
In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
Q: Problem: a is half good a work man as b and together they finish a job in 14 days . in how many days working alone b finish the job ? 
Options: a ) 23 , b ) 22 , c ) 21 , d ) 36 , e ) 48
A:
user
The task is asking you to solve a physics-related word problem involving work and time. Here's a breakdown of the steps to follow and how to use the given information to find the answer.

Step 1: Understand the problem
The problem states that worker A is half as good as worker B in performing a job. Together, they can finish the job in 14 days. Your task is to find out how many days it would take for worker B to finish the job if working alone.

Step 2: Use the given information to set up the equation
Let's use the variables A for worker A's work rate, B for worker B's work rate, and T for the time required for worker B to finish the job alone. Since A is half as good as B, A = 1/2 * B.

Step 3: Set up the equation for combined work
When A and B are working together, their combined work is (A + B) * 14 days = 1 job. Substitute A = 1/2 * B back to the equation: (1/2 * B + B) * 14 = 1.

Step 4: Solve the equation for T (time required for worker B to finish the job alone)
(1/2 * B + B) * 14 = 1
(1.5 * B) * 14 = 1
21 * B = 1
B = 1/21 (Worker B can finish 1/21 of the job in one day)

Since B can finish 1/21 of the job in a day, to complete the job alone, worker B needs:
T = 1 job / (1/21 of job per day)
T = 1 * 21
T = 21 days

Step 5: Find the answer in the given options
Now that we found the time needed for worker B to finish the job alone, look for the corresponding option among the choices provided.

The answer is:
c ) 21
assistant