A 3.0 kg brick rests on a perfectly smooth ramp inclined at 34 above the horizontal. The brick is kept from sliding down the plane by an ideal spring that is aligned with the surface and attached to a wall above the brick. The spring has a spring constant (force constant) of 120 N/m. By how much does the spring stretch with the brick attached?

1 answer

Fb = m*g = 3kg * 9.8N/kg = 29.4 N. = Force of the brick.

Fp = 29.4*sin34 = 16.44 N. = Force parallel to the incline.

d = (16.44/120) * 1m = 0.137 m.