A string of length 5cm is extended by 0.04m when a load of 0.8kg is suspended at the end. How far will it extend if a force of 16N is applied? [g = 10ms−2 −...
A string of length 5cm is extended by 0.04m when a load of 0.8kg is suspended at the end. How far will it extend if a force of 16N is applied? [g = 10ms−2]
Answer Details
The extension of a string when a load is suspended from it is given by Hooke's Law which states that the extension is proportional to the force applied. The proportionality constant is called the spring constant, represented by k. Mathematically, we can express this relationship as:
F = kx
where F is the force applied, x is the extension, and k is the spring constant.
To solve this problem, we need to find the spring constant, k, of the string. We can use the information given in the problem to calculate k as follows:
k = F/x
where F is the force applied and x is the extension.
We are given that the string of length 5cm (which is 0.05m) is extended by 0.04m when a load of 0.8kg is suspended at the end. We can convert the mass to force using the formula F = mg, where g is the acceleration due to gravity (g = 10ms^-2).
F = 0.8kg × 10ms^-2 = 8N
Using the formula for the spring constant, we get:
k = F/x = 8N / 0.04m = 200N/m
Now, we can use this spring constant to find the extension when a force of 16N is applied. Again, we can use the formula F = kx and rearrange it to solve for x:
x = F/k
Plugging in the values, we get:
x = 16N / 200N/m = 0.08m
Therefore, the string will extend by 0.08m when a force of 16N is applied. The answer is (D) 0.08m.