A thin uniform rod of length

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D.

Let P(r) = Qr/πR⁴ be the charge density distribution for a solid sphere of radius R and total charge Q. for a point ‘p’ inside the sphere at distance r₁ from the centre of the sphere, the magnitude of electric field is

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• 0

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C.

A particle has an initial velocity of  and an acceleration of It speed after 10 s

• 10 units

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• 7 units

• 8.5 units

B.

A motorcycle starts from rest and accelerates along a straight path at 2 m/s². At the straight point of the motorcycle, there is a stationary electric siren. How far has the motorcycle gone when the driver hears the frequency of the siren at 94% of its value when the motorcycle was at rest?

• 49 m

• 98 m

• 147 m

• 196 m

B.

98 m

Consider a rubber ball freely falling from a height h = 4.9 m onto a horizontal elastic plate.Assume that the duration of collision is negligible and the collision with the plate is totally elastic.Then the velocity as a function of time and the height as a function of time will be

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C.

When ball strikes the surface its velocity will be reversed therefore correct answer is 3.