Final answer:
Mr. H's displacement from the classroom door is 5 m.
Step-by-step explanation:
To find Mr. H's displacement from the classroom door, we can use the Pythagorean theorem. Mr. H walked 3 m to the right and 4 m towards the back of the classroom. This forms a right triangle with the classroom door as the starting point. The displacement is the hypotenuse of the triangle, which we can find using a^2 + b^2 = c^2.
Applying the formula, (3 m)^2 + (4 m)^2 = c^2, we get 9 m^2 + 16 m^2 = c^2. Simplifying, 25 m^2 = c^2. Taking the square root of both sides, we find that c = 5 m.
Therefore, Mr. H's displacement from the classroom door is 5 m.