Question

A lead fishing weight of a mass of 0.20 kg is tied to a fishing line that is 0.50 m long. The weight is then whirled in a vertical circle. The finishing line will break if its tension exceeds 100.0 N.

Required:
a. If the weight is whirled at higher and higher speeds, at what point in the vertical circle will the string break (top, bottom, or random position)?
b. At what speed will the string break?

Answer 1

Answer:

The solution of the given question is summarized in the below section.

Explanation:

The given values are:

Tension,

T = 100 N

mass,

m = 0.2 kg

length,

l = 0.5 m

Now,

(a)

Somewhere at bottom, string or thread breaks since string voltage seems to be the strongest around this stage.

then,

⇒  $T-mg=\frac{mv^2}{l}$

or,

⇒  $T=mg+\frac{mv^2}{l}$

(b)

As we know,

⇒  $\frac{mv^2}{l}=T-mg$

or,

⇒  $v^2=\frac{(T-mg)l}{m}$

On substituting the values, we get

⇒       $=\frac{(100-0.2\times 10)0.5}{0.2}$

⇒       $=\frac{49}{0.2}$

⇒    $v =\sqrt{245}$

⇒       $=15.65 \ m/s$