Question

A brick of mass 2 kg begins to slide down on a plane inclined at an angle of 45^o with the horizontal. The force of friction will be

• A. 19.6 sin 45^o
• B. 19.6 cos 45^o
• C. 9.8 sin 45^o
• D. 9.8 cos 45^o

Answer 1

Answer: (A)

19.6 sin 45^o

Answer 2

For angle of repose,

Friction =Component of weight along the plane

= $m g \sin \theta$ $= 2 \times 9.8 \times \sin 45 ^ { \circ }$ $= 19.6 \sin 45 ^ { \circ }$