Friction is denoted by the letter . . . . . . .
a) F
b) Fr
c) f
d) fr
Friction is a . . . . . . quantity.
a) vector
b) scalar
c) non-physical
d) none of these
Unit of friction is . . . . . . .
a) kgm/s2
b) newton
c) N
d) all of these
A contact force perpendicular to the contact surface that prevents two objects from passing through one another is called the . . . . . . . force.
a) normal
b) friction
c) gravitational
d) attractive
In geometry, normal means . . . . . .
a) opposite
b) perpendicular
c) parallel
d) tangent
Normal force is . . . . . . to the contact surface.
a) parallel
b) tangent
c) perpendicular
d) none
