An airplane needs to accelerate at 4.7 m/s2 to reach take-off speed before reaching the end of the runway. The mass of the airplane is 4500 kg. How much force is needed from the engines?
Force = rate of change of momentum = mass * acceleration if the mass is constant.
Here you can ignore any change of mass due to fuel exhaust and simply use
F = m a
To calculate the force needed from the engines, we can use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a). In this case, the acceleration is given as 4.7 m/s^2 and the mass of the airplane is 4500 kg.
So, the equation can be written as:
F = m * a
F = 4500 kg * 4.7 m/s^2
Now, we can calculate the force:
F = 21150 N
Therefore, the airplane needs a force of 21150 Newtons from the engines to accelerate at 4.7 m/s^2.