Consider an elliptically shaped rail PQ in the vertical plane with O P = 3 m and O Q = 4 m . A block of mass 1 kg is pulled along the rail from P to Q with a force of 18 N , which is always parallel t

Question

Consider an elliptically shaped rail PQ in the vertical plane with $O P = 3 m$ and $O Q = 4 m$ . A block of mass $1 kg$ is pulled along the rail from $P$ to $Q$ with a force of $18 N$ , which is always parallel to line $PQ$ (see the figure given). Assuming no frictional losses, the kinetic energy of the block when it reaches $Q$ is $(n \times 10)$ joules. The value of $n$ is (take acceleration due to gravity = $10 m s^{- 2}$ )

Answer:

5.00

Solution:

Using work-energy theorem

$W_{m g} + W_{F} = Δ K E$

$- m g h + F d = Δ K E$

$- 1 \times 10 \times 4 + 18 (5) = Δ K E$

$Δ K E = 50$

$∴ n = 5$

TestHub · Accepted Answer

Using work-energy theorem W m g + W F = Δ K E - m g h + F d = Δ K E - 1 × 10 × 4 + 18 5 = Δ K E Δ K E = 50 ∴ n = 5

Physics - W.E.P. Question with Solution | TestHub

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