Answer :
Final answer:
By calculating the car's acceleration using the change in velocity over time, and then applying Newton's second law, force equals mass times acceleration, we deduce the car's mass to be 2000kg. The correct answer is B) 2000kg.
Explanation:
A student asks: A car is traveling on a level highway at a speed of 15m/s. A braking force of 3000 N brings the car to a stop in 10 seconds. The mass of the car is? A) 1500kg B) 2000kg C) 2500kg D) 3000kg E) 45,000kg. To solve this, we use the formula for acceleration, which is acceleration = (final velocity - initial velocity) / time, and Newton's second law, force = mass x acceleration. Given that the final velocity is 0 m/s (since the car stops), and the initial velocity is 15 m/s, we find that the acceleration is -1.5 m/s² (negative because it's deceleration).
Using the given force of 3000 N, and rearranging the equation for Newton's second law to find mass (mass = force / acceleration), and plugging in our values, mass = 3000 N / 1.5 m/s², we get a mass of 2000 kg. Therefore, the correct answer is B) 2000kg.
