Question

The centripetal force required for 1000 kg car travelling at 36 km per hour to take a turn by 90 degrees in travelling along an Arc of length 628 metres is

Answer 1

According to question

Mass M = 1000 Kg
Speed   v = 36 Km/hr

Length or arc travelled  = 628 m

Thus   for 90 deg
Length = 1/2 pi * r  = 628
              22/7 * r = 628 *2
                          r = 400 m

Thus     Centripetal force
       Fc = M v^2/r
           = 1000 * 36 * 36 / 400
            = 3240 N

Answer 2

Given:
Mass=1000kg
Speed=36km/hr =36×5/18=10m/s
Length of arc=L=628m
Formula for length of arc:
L=(90/180)×22/7×r
L=(1/2)×22/7×r
r=7×628×2/22
=7×628/11
=400m
Centripetal force = F= mv^2/r
=1000×10×10/400
=1000/4
=250N