Question

1.The end of a cantilever is depressed by 10 mm under a certain load. Calculate
the depression under the same load for another cantilever of same material,
having dimensions two times in length, two times in width and three times in
thickness.

Answer 1

Answer:

Given :

Heat gained = 4.5 × 10⁵ J

Heat released = 2 × 10⁵ J

To Find :

Percentage efficiency of steam engine and work done per cycle..

Solution :

❒ Efficiency of a heat engine/steam engine is given by, η = 1 - (Q₂ / Q₁)

Where,

η denotes efficiency

Q₂ denotes heat released to the sink

Q₁ denotes heat extracted from the source

By substituting the given values;

➛ η = 1 - (Q₂ / Q₁)

➛ η = 1 - (2 × 10⁵ / 4.5 × 10⁵)

➛ η = 1 - 0.44

➛ η = 0.56

Percentage efficiency = 56%

❒ Work done per cycle :

We know that work done is measured as the change in energy.

➠ W = Q₁ - Q₂

➠ W = (4.5 × 10⁵) - (2 × 10⁵)

➠ W = 2.5 × 10⁵ J