Question

A curve in a road forms part of a horizontal circle. as a car goes around it at constant speed 14.0 m/s, the horizontal total force on the driver has magnitude 146 n. what is the total horizontal force on the driver if the speed on the same curve is 19.8 m/s instead

Answer 1

Because that part of the road is a circle we can use the radial force equation of circular motion
F=mv^2/r
Here we don't know m or r but we can solve for the ratio m/r since we are given the force at a known velocity v. Rewriting with this info:
146=(m/r)(14^2)
146=(m/r)(196)
146/196=m/r
0.745=m/r
Now we use this to get the answer
F=0.745(19.8^2)=292N