Answer:
The magnitude of the unknown force is 44.8 N.
Explanation:
The force can be found with Newton's second law:
[tex] F = ma [/tex]
Where:
m: is the mass of the toy car = 5.5 kg
a: is the acceleration
F: is the force =?
We can calculate the acceleration with the following kinematic equation:
[tex] v_{f}^{2} = v_{0}^{2} + 2ad [/tex]
Where:
[tex] v_{f} [/tex]: is the final speed = 7.3 m/s
[tex] v_{0} [/tex]: is the initial speed = 2.1 m/s
d: is the distance traveled = 3 m
Hence, the acceleration is:
[tex] a = \frac{v_{f}^{2} - v_{0}^{2}}{2d} = \frac{(7.3 m/s)^{2} - (2.1 m/s)^{2}}{2*3 m} = 8.15 m/s^{2} [/tex]
Finally, the magnitude of the force is:
[tex]F = ma = 5.5 kg*8.15 m/s^{2} = 44.8 N[/tex]
Therefore, the magnitude of the unknown force is 44.8 N.
I hope it helps you!