Question

Which has more kinetic energy:

a. A compact car going 70 MPH or a tractor trailer going 15 MPH?
b. An SUV going 30 MPH or a pickup truck going 30 MPH?
c. A school bus going 15 MPH, an SUV going 35 MPH, or a
compact car going 45 MPH?

Answer 1

Step-by-step explanation:

a. The compact car going 70 MPH has more kinetic energy than the tractor trailer going 15 MPH. Kinetic energy is proportional to the square of the velocity, so even though the tractor trailer may have more mass, the higher velocity of the compact car results in greater kinetic energy.

b. The SUV and the pickup truck have the same kinetic energy since they have the same mass and velocity.

c. The compact car going 45 MPH has the most kinetic energy since it has the highest velocity out of the three vehicles. The SUV going 35 MPH has less kinetic energy, and the school bus going 15 MPH has the least kinetic energy.