Driving in your car with a constant speed of v= 22 m/s, you encounter a bump in the road that has a circular cross-section, as indicated in the figure.
If the radius of curvature of the bump is 52 m, find the apparent weight of a 66-kg person in your car as you pass over the top of the bump.
2 answers
Knowing the radius of the circle is not enough. Is it a full semi-circle, or a smaller section? A speed bump 1cm high will not do much.
m= 66kg
v= 22 m/s
r= 52m
ΣF (c) = m*a (c) = m*v^2/r = m*g-n
n=m*g - m*v^2/r
n= m (g - v^2/r)
= 66kg [ 9.81 m/s^2 - (22 m/s)^2 / 52m]
=66kg [9.81 m/s^2 - (484 m^2/ s^2) / 52m]
=66kg (9.81 m/s^2 - 9.31 m/s^2)
=66 kg (0.5 m/s^2)
=33 N
v= 22 m/s
r= 52m
ΣF (c) = m*a (c) = m*v^2/r = m*g-n
n=m*g - m*v^2/r
n= m (g - v^2/r)
= 66kg [ 9.81 m/s^2 - (22 m/s)^2 / 52m]
=66kg [9.81 m/s^2 - (484 m^2/ s^2) / 52m]
=66kg (9.81 m/s^2 - 9.31 m/s^2)
=66 kg (0.5 m/s^2)
=33 N