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Lana71 [14]
3 years ago
10

An object of mass 2 kg starts from rest and is allowed to slide down a

Physics
1 answer:
WARRIOR [948]3 years ago
7 0

Answer: B

Explanation:

Given that an object of mass 2 kg starts from rest and is allowed to slide down a frictionless incline so that its height changes by 20 m. 

The parameters given from the question are:

Mass M = 2kg

Height h = 20m

Let g = 9.8m/s^2

At the bottom of the incline plane, the object will experience maximum kinetic energy.

From conservative of energy, maximum K.K.E = maximum P.E

Maximum P.E = mgh

Maximum P.E = 2 × 9.8 × 20 = 392 J

But

K.E = 1/2mv^2

Substitute the values of energy and mass into the formula

392 = 1/2 × 2 × V^2

V^2 = 392

V = sqrt( 392 )

V = 19.8 m/s

V = 20 m/s approximately

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Answer:

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F = Qqs/4πε₀r³

b)  the magnitude of the torque on the dipole

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Explanation:

from coulomb's law

E = \frac{kq}{r^{2} }

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the expression of the electric field due to dipole at a distance r is

E(r) = \frac{kp}{r^{3} } , where p = q × s

E(r) = \frac{kqs}{r^{3} } where r>>s

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where k = 1/4πε₀

F = Qqs/4πε₀r³

b) b) magnitude of the torque(τ) on the dipole is dependent on the perpendicular forces

τ = F sinθ × s

θ = 90°

note: sin90° = 1

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∴ τ = (Qqs/4πε₀r³) × r

τ = Qqs/4πε₀r²

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3 years ago
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Given that,

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Answer:

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