A 1000-kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is? On this question I asked my teacher I am suppose to get 2000 N and I don't get how to get it.
you are right it is 2000 N. cuz, you can compute the acceleration by noting that the acceleration is the change in time.
a= (10 m/s-0 m/s)/5 s=m/s^2
To find the average braking force, you can use Newton's second law of motion, which states that the force acting on an object is equal to the mass of the object multiplied by its acceleration. In this case, the object is the car, and the acceleration is the change in velocity divided by the time taken.
First, let's calculate the acceleration of the car. The car is going from 10 m/s to 0 m/s in 5 seconds, so the change in velocity is 10 m/s. Dividing this by the time taken, which is 5 seconds, we get:
Acceleration = (Final Velocity - Initial Velocity) / Time
Acceleration = (0 m/s - 10 m/s) / 5 s
Acceleration = -10 m/s / 5 s
Acceleration = -2 m/s²
Note that the negative sign indicates deceleration or slowing down.
Now, let's use Newton's second law to find the average braking force. The formula is:
Force = Mass × Acceleration
We know the mass of the car is 1000 kg, and the acceleration is -2 m/s². Substituting these values into the formula, we get:
Force = 1000 kg × (-2 m/s²)
Force = -2000 N
The negative sign indicates that the force is opposite to the direction of motion (opposite to the velocity) and represents the deceleration force acting on the car.
Therefore, the correct answer is -2000 N, and not 2000 N as you mentioned.
To solve this question, you can use Newton's second law of motion, which states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration.
In this case, the car is initially moving with a velocity of 10 m/s and comes to a stop in 5 seconds (final velocity is 0). Therefore, the car's acceleration can be calculated by using the formula:
Acceleration = (Final Velocity - Initial Velocity) / Time
Acceleration = (0 - 10 m/s) / 5 s
Acceleration = -10 m/s^2
Since the car is braking, the acceleration is negative.
Now, you can calculate the average braking force by using Newton's second law of motion:
Force = Mass * Acceleration
Force = 1000 kg * -10 m/s^2
Force = -10,000 N
The negative sign indicates that the force is in the opposite direction to the motion of the car. To obtain the magnitude of the force, you can take the absolute value:
Average Braking Force = |-10,000 N| = 10,000 N
Therefore, the average braking force exerted on the car is 10,000 Newtons, not 2000 Newtons as stated by your teacher.