Question

A cart of mass 1000 kg is pulled by a horse of 200kg. The coefficient of friction between them and ground is 0.2. Calculate the force required to produce acceleration of 2 m/s^2 in the cart??'

Answer 1

`F_"pull" = 3960 N`

Explanation:

The net force required to give the cart acceleration of `2 m/s^2` is given by

`F_"net" = m*a = 1000 kg*2 m/s^2 = 2000 kg*m/s^2 = 2000 N`

The friction between the cart and the ground will be in the opposite direction of the pull on the cart.

The friction, `F_f`, will be

`F_f = mu_k*N = 0.2*m*g = 0.2*1000 kg*9.8 m/s^2`

`F_f = 1960 kg*m/s^2 = 1960 N`

Therefore, the `2000 N` net force is the resultant of the 2 forces on the cart.

#F_"net" = 2000 N = F_"pull" - F_f = F_"pull" - 1960N

`2000 N = F_"pull" - 1960N`

`F_"pull" = 2000 N + 1960 N = 3960 N`

... Assuming level ground.

I hope this helps,
Steve