Question

Five persons A, B, C, D& E are pulling a cart of mass 100 kg on a smooth surface and cart is moving with acceleration $3m/s^2$ in east direction. When person ‘A’ stops pulling, it moves with acceleration $1m/s^2$ in the west direction. When only person ‘B’ stops pulling, it moves with acceleration $24m/s^2$in the north direction. The magnitude of acceleration of the cart when only A & B pull the cart keeping their directions same as the old directions, is $\left(25/n\right)m/s^2,$ value of n is ___

• A. 1

Answer 1

The correct option is A

1

When all are pulling
${\overrightarrow{F}}_{nBt}=100\times 3\hat{i}$ ...(1)
When 'A' stops
${\overrightarrow{F}}_{nBt}=-{\overrightarrow{F}}_A=100\times 1(-\hat{i})$ ...(2)
When 'B' stops
${\overrightarrow{F}}_{nBt}=-{\overrightarrow{F}}_B=100\times 24(-\hat{j})$
From these three get
${\overrightarrow{F}}_A+{\overrightarrow{F}}_B$ and solve