- #1
EricPowell
- 26
- 0
Homework Statement
A car traveling at 88ft/s skids 176ft after its brakes are applied. The deceleration provided by the braking system is constant. What is its value?
The Attempt at a Solution
$$
v_0=88 \\
v_f=0 \\
d_0=0 \\
d_f=176
$$
$$
d(t)=\int88\,dt \\
d(t)=88t+c \\
0=88(0)+C \\
C=0 \\
176=88t \\
t=2s
$$
$$
a=\frac{Δv}{Δt} \\
=\frac{-88}{2} \\
=-44ft/s
$$
The answer key of the textbook says that the deceleration is -22ft/s2. :(