Answer :
Final answer:
The 900 kg compact car must travel at 25 m/s to have the same kinetic energy as a 20,000 kg truck going 25 km/h.
Explanation:
To find out at what speed the 900 kg compact car must travel to have the same kinetic energy as a 20,000 kg truck going 25 km/h, we can use the formula for kinetic energy, KE = 0.5 × m × v^2. Firstly, let's convert the truck's speed to meters per second (25 km/h × 1000 m/km) / (3600 s/h) = 6.94 m/s.
Then we calculate the truck's kinetic energy, KE = 0.5 × 20000 kg × (6.94 m/s)^2. To find the car's speed (v), we set the kinetic energies equal: 0.5 × 900 kg × v^2 = 0.5 × 20000 kg × (6.94 m/s)^2, and solve for v. The equation simplifies to v = sqrt((0.5 × 20000 kg × (6.94 m/s)^2) / (0.5 × 900 kg)), which gives a solution around 25 m/s.
Therefore, the compact car must travel at 25 m/s to have the same kinetic energy as the truck.
