Question

a 70 kg man pushes a 50kg man by 50n. what force has the 50kg man push the other man.

Answer 1

HELLO DEAR,

GIVEN,

70kg person pushes a 50kg man by a force of 50N .


So, Let force = 50N

now, normal reaction act on 50 kg man = mg

mg = 500N

we know, friction is directly proportional to normal reaction then,

fr = kN ,
k is coefficient of static friction and N is normal reaction.

now, for balancing fr = F

so, 50 = kN

50 = k × 500

k = 50/500

K = 0.1 ,

hence coefficient of static Friction = 0.1

Let F' force act by 50kg man on 70 kg man

then, F' = static Friction act on 70kg man

= coefficient of static friction × normal reaction act on 70 kg man

= 0.1 × 70 × 10 [ g = 10 m/s² ]

= 70N.


I HOPE ITS HELP YOU DEAR,
THANKS

Answer 2

Given in the question :-

Here, Mass of the man = 70 kg

⇒(F) Force used by the man to push another man of mass 50 kg = 50 N.

⇒Normal reaction act on 50 kg man = mass × acceleration due to gravity.

= 50 × 10 N

500 N

Using the Formula, Friction = r N ,

where,

N is normal reaction,

r is coefficient of static friction

Here, In Ideal Condition, Frictional Force = Normal Reaction Force.

∴ 50 = r × N

50 = r × 500

so, r = 0.1

Therefore, coefficient of static Friction = 0.1

Assuming Force acting on the man of mass 50 kg by the man of mass , 70 kg be x.

Therefore, x = static Friction

Here, x = coefficient of static friction × normal reaction act on 70 kg man

Now,

x = 0.1 × 70 × 10

x = 70 N

Thus, the Force of 70 N acts as on the body of mass 50 kg by the man of 70 kg is = 70 N.

Hope it helps.