Work Energy And Power Question 1
Question: Read the assertion and reason carefully to mark the correct option out of the options given below: Assertion : A person working on a horizontal road with a load on his head does no work. Reason : No work is said to be done, if directions of force and displacement of load are perpendicular to each other.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: A
Solution:
The work done, $ W=\overrightarrow{F}.\overrightarrow{s}=Fs\cos \theta $ ,
when a person walk on a horizontal road with load on his head then $ \theta =90{}^\circ $ .
Hence $ W=Fs\cos 90{}^\circ =0 $ Thus no work is done by the person.
