Question

On an alien planet, an object moving at 4.0 m/s on the horizontal ground comes to rest after traveling a distance of 10 m. If the coefficient of kinetic friction between the object and the surface is 0.20, what is the value of g on that planet?

Answer 1

Answer:

So acceleration due to gravity is $4m/sec^2$

Explanation:

We have given initial speed of the object u = 4 m/sec

As object finally comes to rest so final speed v = 0 m./sec

Distance traveled s = 10 m

From third equation of motion we know that $v^2=u^2+2as$

$0^2=4^2+2\times a\times 10$

$a=-0.8m/sec^2$

Coefficient of kinetic friction $\mu _k=0.2$

We know that relation between acceleration and coefficient of kinetic friction

$a=\mu _kg$

$g=\frac{a}{\mu _k}=\frac{0.8}{0.2}=4m/sec^2$

So acceleration due to gravity is $4m/sec^2$