Laws of Motion - Result Question 35
35. A mass of $1 kg$ is suspended by a thread. It is (i) lifted up with an acceleration $4.9 m / s^{2}$, (ii) lowered with an acceleration $4.9 m / s^{2}$. The ratio of the tensions is
[1998]
(a) $3: 1$
(b) $1: 2$
(c) $1: 3$
(d) $2: 1$
Show Answer
Answer:
Correct Answer: 35. (a)
Solution:
- (a) In case (i) we have
$ \begin{aligned} & T_1-(1 \times g)=1 \times 4.9 \\ & \Rightarrow T_1=9.8+4.9=14.7 N \end{aligned} $
In case (ii), $1 \times g-T_2=1 \times 4.9$
$\Rightarrow T_2=9.8-4.9=4.9 N$
$\therefore \frac{T_1}{T_2}=\frac{14.7}{4.9}=\frac{3}{1}$
