Question

After an initial race George determines that his car loses 35 percent of its acceleration due to air resistance travelling at 38 m/s on flat ground. Assuming that his car travels with a constant acceleration, calculate the maximum speed (Vm), in meters per second, his car can reach on flat ground?\

Answer 1

Answer:

64.2 m/s

Explanation:

We are given that

Speed ,v=38 m/s

We have to find the maximum speed when his car reach on flat ground.

Using dimensional analysis

$F_{res}\propto v^2$

If 35% acceleration reduced by F(res) at 38 m/s

Then, 100% acceleration  can be reduced  by F(res) at v' m/s

$\frac{F_1}{F_2}=\frac{v^2}{v'^2}$

$v'^2=\frac{F_2}{F_1}v^2$

$v'=v\sqrt{\frac{F_2}{F_1}}$

Substitute the values

$v'=38\times \sqrt{\frac{100}{35}}$

$v'=64.2 m/s$

Hence, the maximum speed when his car can reach on flat ground=64.2 m/s