An object moves in uniform circular motion at 25 m/s and takes 1.0 seconds to go a quarter circle, calculate the centripetal acceleration

Centripetal acceleration can be calculated through the equation:

Ac=V^2/r

V is given as 25 m/s, and r can be calculated through using C=pi•d, but we need the circumference first.

25 meters/s to make one quarter turn = 100 meters total circumference

C=pi•d
100=pi•d
d=31.83 meters

Notice that the equation for Ac asks for radius, which can be calculated by dividing the diameter by two (31.83/2 = 15.92).

Ac=V^2/r
Ac=(25^2)/15.92
Ac=39.26 Newtons

The centripetal acceleration of this object would be approximately 39.26 Newtons (re-run this calculation set with a calculator because rounding was heavily utilized).

The answer is d) by requesting advice on science internet sites