Question 73
In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2.
A box of mass 12 kg is pulled along a rough horizontal floor by a force of magnitude 20 N acting at an angle of 25° 25°\,25° above the horizontal. The box is modelled as a particle and the coefficient of friction between the box and the floor is 0.1.
a.[5]
Find the acceleration of the box.
b.[2]
The box is now pushed along the same floor by a force of magnitude 20 N acting at an angle of 25° 25°\,25° below the horizontal. Explain why the acceleration of the box will now be less than the acceleration in part (a).
