To solve this problem it is necessary to apply the concepts related to Newton's second Law and the force of friction. According to Newton, the Force is defined as
F = ma
Where,
m= Mass
a = Acceleration
At the same time the frictional force can be defined as,

Where,
Frictional coefficient
N = Normal force (mass*gravity)
Our values are given as,

By condition of Balance the friction force must be equal to the total net force, that is to say



Re-arrange to find acceleration,



Therefore the acceleration the horse can give is 
Answer:
W = 6642 J
Explanation:
Given that,
Mass of a crate, m = 67 kg
Force with which the crate is pulled, F = 738 N
It is moved 9 m across a frictionless floor
We need to find the work done in moving the crate. Let the work done is W. It is given by :
W = F d
W = 738 N × 9 m
= 6642 J
So, the work done is 6642 J.
Answer:
The mass of the cart is 150 kg.
Explanation:
Given that,
Mass of a boy, m₁ = 50 kg
Initial speed of boy, u₁ = 10 m/s
Initial speed of car, u₂ = 0 (at rest)
The speed of the cart with the boy on it is 2.50 m/s, V = 2.5 m/s
Let m₂ is the mass of the cart. Using the conservation of momentum as follows :

So, the mass of the cart is 150 kg.