Compute the total force which shall be acting on the springs:
An automobile of mass 1300 kg, travelling at a speed of 60 kmph hits a depression in the road that has a radius of curvature of 15 m. Compute the total force which shall be acting on the springs.
Solution
The speed of the car is 60 kmph, i.e.
(60 × 1000)/3600
= 16.67 m / sec
The car is travelling along with a curve of radius 15 m. Hence, acceleration
an = v2 / r .
∴ an = (16.67)2/ 15
= 18.52 m / sec
The inertia force Fi = - m an shall be acting as illustrated.
∴ Fi = - m . an = 1300 × 18.52
= 24076 N
Considering equilibrium of forces as illustrated in Figure (b), we obtain following
∑ Fy = 0 ∴ N = Fi + mg
= 24076 + 12753 = 36829 N ;
where mg = 1300 × 9.81