CBSE Class 10 Maths (Basic) 2024 · Paper 430/S/1 · Question 38

Some Applications of Trigonometry 4 marks Very hard

A short circuit can happen on electric poles due to several reasons, like

(a)if the insulation is damaged or old, it may allow the hot wires to touch with neutral. This will cause a short circuit.
(b)if there are any loose wire connections or attachments, it will allow the live and neutral wires to touch. An electrician has to repair an electric fault on a pole of height 5 m. He needs to reach a point 1 m below the top of the pole to undertake the repair work.

Electrician on a ladder against the pole at 60 degrees

Pole AD with ladder BC at 60 degrees; B is 4 m above the ground

(i)What should be the length of the ladder that he should use which, when inclined at an angle of $6 0^{\circ}$ to the horizontal, enables him to reach the required position?[2]
(ii)(a)How far from the foot of the pole should he place the foot of the ladder?[2]
(ii)(b)What is the length of the ladder if its foot is kept at a distance of 4 m from the foot of the pole?[2]

Answer

(i) The ladder should be

\frac{8 3}{3} m \approx 4.62

m long; (ii)(a) Its foot should be

\frac{4 3}{3} m \approx 2.31

m from the foot of the pole; (ii)(b) The ladder is

42 m \approx 5.66

m long.

🔒 Step-by-step solution