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प्रश्न
How can you find the following?
Acceleration from velocity – time graph.
उत्तर
Acceleration from velocity – time graph: Velocity – time graph for uniform motion in a straight line (OP) inclined to the time axis.
Take any two points A and B on this graph. From A and B draw perpendicular on the time axis as well as velocity axis in such a way that
OA1 = t1, OB1 = t2, OA2 = v1 and OB2 = v2
Slope of v – t graph = `"BC"/"AC"`
= `("v"_2-"v"_1)/("t"_2-"t"_1)=(Δ"v")/(Δ"t")` = Acceleration of the body
So, by knowing the slope of velocity – time graph for uniform motion, we can find the acceleration of the body.
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संबंधित प्रश्न
Fill in the following blank with a suitable word:
Acceleration is the rate of change of ______ It is measured in ______
Find the initial velocity of a car which is stopped in 10 seconds by applying brakes. The retardation due to brakes is 2.5 m/s2.
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A cheetah starts from, rest, and accelerates at 2 m/s2 for 10 seconds. Calculate :
(a) the final velocity
(b) the distance travelled.
Give one example of following motion :
Variable acceleration
Derive the following equations for uniformly accelerated motion:
(i) v = u + at
(ii) `"S = ut" + 1/2 "at"^2`
(iii) v2 = u2 + 2aS
where the symbols have their usual meanings.
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At the maximum height, a body thrown vertically upwards has :
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(i) Calculate the time in which the electron would acquire a velocity double of its initial velocity.
(ii) How much distance the electron would cover at this time?
