Answer:
Force of friction is (-30 N).
Explanation:
The force applied on the box across the floor is 30 N.
The force of gravity is (-8 N) and the the normal force is 8 N.
It is based on Newton's third law of motion. Newton's third law of motion states that the force acting on object 1 to object 2 is equal in magnitude of the force from object 2 to 1 but in opposite direction.
Here there is force of 30 N is applied in horizontal direction. The frictional force act in opposite direction. So, the force of friction is -30 N so that box across the floor.
KE= .5*M*V^2
.5*.5*10^2
=25Joules
m₁ = mass of the first object = 3.0 kg
m₂ = mass of the second object = 3.0 kg
r = distance between the first and second object = 1.0 m
G = universal gravitational constant = 6.67 x 10⁻¹¹ N m²/kg²
F = force of gravity between the two objects = ?
according to law of gravitation, force of attraction "F" between two objects m₁ and m₂, placed distance "r" apart is given as
F = G m₁ m₂/r²
inserting the values
F = (6.67 x 10⁻¹¹) (3.0) (3.0)/(1.0)²
F = (6.67 x 10⁻¹¹) (9.0)
F = 60.03 x 10⁻¹¹ N
F = 6.003 x 10⁻¹⁰ N
3.25 x 10^2 (ten to the second power)
