Question

Two skaters, a man and a woman, are standing on ice. Neglect any friction between the skate blades and the ice. The mass of the man is 81 kg, and the mass of the woman is 49 kg. The woman pushes on the man with a force of 46 N due east. Determine the acceleration (magnitude and direction) of the following.

(a)the man aman =

(b)the woman awoman =

Answer 1

We have to use Newton's Third law to solve this problem, the Third Law states that for every action, there is an opposite and equal reaction. Action and reaction here means the forces and 'opposite' means the direction of the reaction.

a) Lets say the woman applies a force on the man which is 46N towards East,but there will be an opposite and equal force acting on the woman accoring to the Third Law

ie, , (where is the reaction force on the woman)

Since F1 is acting on the man, (m1 is the mass of the man which is 81kg)

therefore, due east

b) Similarly for the woman's case, (m2=49kg)

But, according to the third law,

therefore,

which implies, due east

We have a negative acceleration due east, which means the woman has an acceleration of due west