Answer:
B) Force of gravity
Explanation:
As it is the force which acts downward on the body towards the ground, it is clearly the force gravity represented by the arrow at A.
a). Water is still H₂O after it freezes.
b). Ice is still H₂O after it melts.
c). Wire is still Cu when it's bent.
d). Paper combines with the O₂ in the air, and turns into
a lot of new compounds when it burns.
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,
![F_f = \mu N](https://tex.z-dn.net/?f=F_f%20%3D%20%5Cmu%20N)
Where,
Frictional coefficient
N = Normal force (mass*gravity)
Our values are given as,
![m_h = 242 kg\\m_c = 224 kg\\\mu = 0.894\\](https://tex.z-dn.net/?f=m_h%20%3D%20242%20kg%5C%5Cm_c%20%3D%20224%20kg%5C%5C%5Cmu%20%3D%200.894%5C%5C)
By condition of Balance the friction force must be equal to the total net force, that is to say
![F_{net} = F_f](https://tex.z-dn.net/?f=F_%7Bnet%7D%20%3D%20F_f)
![m_{total}a = \mu m_hg](https://tex.z-dn.net/?f=m_%7Btotal%7Da%20%3D%20%5Cmu%20m_hg)
![(m_h+m_c)a = \mu*m_h*g](https://tex.z-dn.net/?f=%28m_h%2Bm_c%29a%20%3D%20%5Cmu%2Am_h%2Ag)
Re-arrange to find acceleration,
![a= \frac{\mu*m_h*g}{(m_h+m_c)}](https://tex.z-dn.net/?f=a%3D%20%5Cfrac%7B%5Cmu%2Am_h%2Ag%7D%7B%28m_h%2Bm_c%29%7D)
![a = \frac{0.894*242*9.8}{(242+224)}](https://tex.z-dn.net/?f=a%20%3D%20%5Cfrac%7B0.894%2A242%2A9.8%7D%7B%28242%2B224%29%7D)
![a = 4.54 m/s^2](https://tex.z-dn.net/?f=a%20%3D%204.54%20m%2Fs%5E2)
Therefore the acceleration the horse can give is ![4.54m/s^2](https://tex.z-dn.net/?f=4.54m%2Fs%5E2)