Question

A light spring has a force constant of 70 N/m and is used to pull a 10 kg box on a horizontal frictionless surface. If the box has an acceleration of 5

m/s2, by how much does the spring stretch if it pulls on the sled at 30.0° above the horizontal?
88.9 cm
50.7 cm
82.4 cm
66.3 cm

Answer 1

82.4 cm

Step-by-step explanation:

∑F = ma

kx cos θ = ma

x = ma / (k cos θ)

x = (10 kg) (5 m/s²) / (70 N/m cos 30.0°)

x = 0.824 m

x = 82.4 cm