Question

A 40%-efficient car engine accelerates the 1200 kg car from rest to 12 m/s . part a how much energy is transferred to the engine by burning gasoline? express your answer in kilojoules.

Answer 1

The energy transferred to the engine by burning gasoline is 216 kilojoules.

Step-by-step explanation:

To find the energy transferred to the engine by burning gasoline, we need to calculate the kinetic energy gained by the car when it accelerates. The formula for kinetic energy is:

KE = \frac{1}{2} mv^2

where KE is the kinetic energy, m is the mass of the car, and v is the final velocity of the car.

Given:

• Mass of the car, m = 1200 kg
• Final velocity of the car, v = 12 m/s
• Efficiency of the car engine, 40%

First, we calculate the kinetic energy using the formula:

KE = \frac{1}{2} \times 1200 \times (12)^2

KE = 86400 J

Next, we divide the kinetic energy by the efficiency of the car engine to find the energy transferred to the engine:

Energy = \frac{KE}{0.40}

Energy = \frac{86400}{0.40}

Energy = 216000 J

Finally, we convert the energy to kilojoules:

Energy = \frac{216000}{1000}

Energy = 216 kJ

Therefore, the energy transferred to the engine by burning gasoline is 216 kilojoules.