Derive the unit of force using the second law of motion. A force of 5N produces an acceleration of 8 m s–2 on a mass m1 and an acceleration of 24 m s–2 on a mass m2. What acceleration would the same force provide if both the masses are tied together?
We know,
Force = mass× acceleration
Unit of mass = kg
Unit of acceleration = m/s2
Therefore, unit of force = kg m/s2
1 kg m/s2 = 1 N
Given, F = 5 N, mass = m1
Acceleration, a = 8 m/s2
F = m × a
m1 = 
kg
Similarly, given F = 5N
Mass = m2
a = 24 m/s2
5 = m2 × 24 m/s2
m2 = 
kg
If both the masses are tie together,
Total mass = 
kg
Now, acceleration for mass 
kg
F = 5 N
F = m × a
a = 
= 6 m/s2
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