**A : To investigate how P varies with Q keeping Z constant**

B: Diagram

B: Diagram

**C:**

**Procedure:**

1. Set up

2. Measure P using M

3. Measure Q using N

4. Repeat steps 2 to 3 by varying P to obtain 6 sets of P and Q keeping Z constant.

5. Calculate R using the formula ...

6. Plot a graph of ln P vs ln Q assuming .....the gradient = n and intercept = lnk

**D: Safety precautions**

**E: Reliability:**

1.How you measure P and Q accurately

2.How you keep Z constant .

3.Any other variables kept constant.

4.Check question for any unanswered parts from a) to e) .