It does the same amount of work in less time.
Explanation
In physics, Power is defined as the time rate at which work is done or energy is transferred. It measures how quickly energy is converted (e.g., from fuel to kinetic energy). The mathematical relationship is:
$P = \frac{W}{t}$
Where $P$ is Power, $W$ is Work, and $t$ is Time.
Detailed Analysis:
- It does the same amount of work in less time. is Correct: According to the Work-Energy Theorem, accelerating a car to a specific speed requires a fixed amount of work (change in kinetic energy). Since Power is the rate of doing work ($P = W/t$), a more powerful engine (higher $P$) can perform the same amount of work ($W$) in a shorter time interval ($t$). A shorter time to reach a specific speed implies faster acceleration.
- It exerts a larger force. is Incorrect: While a powerful engine allows for a larger force to be maintained at a given velocity ($P = F \times v$), the defining characteristic of "power" is the rate of energy transfer. Force is the cause of acceleration ($F=ma$), but power explains the capacity to deliver that force over time to build speed.
- It has more mass. is Incorrect: Mass is a physical property of the engine, not a definition of its performance output. A heavier engine increases the total mass of the vehicle, which could theoretically decrease acceleration if the power-to-weight ratio is not optimized.
- It consumes less fuel. is Incorrect: A more powerful engine typically consumes more fuel per unit time to generate the higher energy output required for rapid acceleration.
Key Takeaway:
Power quantifies the speed of work execution. A more powerful engine accelerates a car faster because it supplies the required kinetic energy in less time.