A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches the box starts to slip and slides 4.0m down the plank in 4.0s. The coefficients of static and kinetic friction between the box and the plank will be, respectively:
0.6 and 0.5
0.5 and 0.6
0.4 and 0.3
0.6 and 0.6
As we discussed in concept
Angle of Friction -
Angle is called angle of friction.
R = Reaction,
Force of limiting friction
- wherein
static friction coefficient
Angle made by resultant of limiting friction and R with the normal reaction.
Option 1)
0.6 and 0.5
This option is correct.
Option 2)
0.5 and 0.6
This option is incorrect.
Option 3)
0.4 and 0.3
This option is incorrect.
Option 4)
0.6 and 0.6
This option is incorrect.