Question

If the mass of truck is 100 times greater than that of the car find the ratio of velocity of the truck to that of car if kinetic energy is equal

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