A dynamometer with a constant elasticity of 200 N / m is placed with a mass of 4 kg. Calculate length.

Question

A dynamometer with a constant elasticity of 200 N / m is placed with a mass of 4 kg. Calculate length.

Answer 1

Assuming you are talking about a mass hanging on a dyamometer, the mass would have a force calculated from F = ma, where "a" is the acceleration due to gravity of 9.81 m/s². So F = (4)(9.81) = 39.24 N

Using Hooke's Law, F = kx, we can solve for x by dividing both sides by k. So, x = F/k (where k is the spring constant noted as 200 N/m and F is the calculated force).

x = F/k

x = (39.24 N)/200 N/m) = 0.1962 meters. Since there is only 1 significant figure in the "givens", we would round the answer to x = 0.2 m

Answer 2

Hello Bimbola!

First remember that:

Weight = mg (Newton's Second Law)

Let's consider g = 10 m/s²

So weight = 4*10 = 40N

The formula of elastic force is:

F = -k*L (the negative sigh just means the force acts in the opposite direction of the length)

40 = 200*L

L = 1/5 m

L = 0.2 m = 20cm

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