Vectors Question 3
Question: A truck travelling due north at 20 m/s turns west and travels at the same speed. The change in its velocity be
[UPSEAT 1999]
Options:
A) 40 m/s NW
B) $ 20\sqrt{2}, $ m/s NW
C) 40 m/s SW
D) $ 20\sqrt{2} $ m/s SW
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Answer:
Correct Answer: D
Solution:
From figure $ {{\overrightarrow{v}}_1}=20\hat{j} $ and $ {{\overrightarrow{v}}_2}=-20\hat{i} $
$ \Delta \overrightarrow{v}={{\overrightarrow{v}}_2}-{{\overrightarrow{v}}_1}=-20(\hat{i}+\hat{j}) $
$ |\Delta \overrightarrow{v}|,=,20\sqrt{2} $ and direction $ \theta ={{\tan }^{-1}}(1)=45{}^\circ $ i.e. S?W
BETA
