Question

A 0.83-kg block is hung from and stretches a spring that is attached to the ceiling. A second block is attached to the first one, and the amount that the spring stretches from its unstretched length triples. What is the mass of the second block?

Answer 1

Answer:

1.66 kg

Explanation:

Given that a 0.83-kg block is hung from and stretches a spring that is attached to the ceiling.

From Hook's law

F = Ke

But F = mg

Substitute mg for force in the Hook's law

Mg = ke

0.83 × 9.8 = ke

Make K the subject of formula

8.134 = Ke

K = 8.134 /e

Given that a second block is attached to the first one, and the amount that the spring stretches from its unstretched length triples.

That is

(0.83 + M) × 9.8 = K (3e)

Substitutes K into the above equation

(0.83 + M) × 9.8 = 8.134 / e (3e)

The e will cancel out

(0.83 + M) × 9.8 = 24.402

0.83 + M = 24.402/9.8

0.83 + M = 2.49

M = 2.49 - 0.83

M = 1.66 kg

Therefore, the mass of the second block is 1.66kg