Question

The reading on a spring balance with a holder and eight identical discs is $3.0N$. Six discs are removed and the reading becomes $1.2N$. What is the weight of one disc?

• A. $0.2N$
• B. $0.3N$
• C. $0.5N$
• D. $0.6N$

Answer 1

The correct option is B $0.3N$

$\text{Reading of spring balance with}8\text{discs}=3N$$=1\cdot 2N$

$loss\text{in weight = Weight of the removed discs}$$=(3-1.2)N=1.8N$

$\begin{array}{c}\\ \text{Weight of}6\text{discs}=1.8N\\ \text{Weight of}1\text{discs}=\frac{1.8}{6}\\ =0.3N\end{array}$