Which of the following has a higher kinetic energy?
A 1000 kg car rolling at a speed of 5 m/s across the floor or a 1500 kg hippo swimming at a speed of 2 m/s
a
the hippo
b
the car
c
their kinetic energies are equal
d
not enough information to determine
Mass of the car = 1000 kg
Speed of the car = 5 m/s
Mass of the hippo = 1500 kg
Speed of the hippo = 2 m/s
The kinetic energy of an object can be calculated using the formula: KE = 0.5 * mass * velocity^2
For the car:
KE = 0.5 * 1000 * 5^2 = 0.5 * 1000 * 25 = 12500 J
For the hippo:
KE = 0.5 * 1500 * 2^2 = 0.5 * 1500 * 4 = 3000 J
Comparing the kinetic energies:
12500 J (car) > 3000 J (hippo)
Therefore, the car has a higher kinetic energy. The correct answer is b) the car.