The distance time graph of a particle at time $$t$$ makes angles $${45^ \circ }$$ with the time axis. After one second, it makes angle $${60^ \circ }$$ with the time axis. What is the acceleration of the particle?
A.
$$\sqrt 3 - 1$$
B.
$$\sqrt 3 + 1$$
C.
$$\sqrt 3 $$
D.
$$1$$
Answer :
$$\sqrt 3 - 1$$
Solution :
Velocity at time $$t$$ is $$\tan {45^ \circ } = 1.$$ Velocity at time $$\left( {t = 1} \right)$$ is $$\tan {60^ \circ } = \sqrt 3 .$$ Acceleration is change in velocity in one second $$ = \sqrt 3 - 1.$$
Releted MCQ Question on Basic Physics >> Kinematics
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