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3 years ago

A ball of mass 12 kg is released from a height of 2.5 m

Physics

1 answer:

VMariaS [17]3 years ago

4 0

Answer:

300 J

Explanation:

From conservation of energy;

Gravitational potential energy at top = Kinetic Energy at bottom

mgh = ½mv²

We are given;

Mass; m = 12 kg.

Height; h = 2.5 m

g = 10 m/s²

Thus;

mgh = 12 × 2.5 × 10 = 300 J

Since mgh = Kinetic Energy at bottom.

Thus; kinetic energy of the ball once it reach the ground = 300 J

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Answer:

$2.46\cdot 10^5 J$

Explanation:

The energy of a single photon is given by:

$E=\frac{hc}{\lambda}$

where

h is the Planck constant

c is the speed of light

$\lambda$ is the wavelength

For the photon in this problem,

$\lambda=486 nm=4.86\cdot 10^{-7}m$

So, its energy is

$E_1=\frac{(6.63\cdot 10^{-34} Js)(3\cdot 10^8 m/s)}{4.86\cdot 10^{-7}m}=4.09\cdot 10^{-19} J$

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The first one it's very windy today and will rain later.

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4 years ago

A capacitor consists of two parallel plates, each with an area of 17.0 cm2 , separated by a distance of 0.150 cm . The material

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Answer:

a) $C = 40.138\,pF$ , b) $q = 16.056\,nC$ , c) $U = 3.212\,\mu J$

Explanation:

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$C = K\cdot \epsilon_{o}\cdot \frac{A}{d}$

Where:

$K$ - Dielectric constant.

$\epsilon_{o}$ - Vaccum permitivity.

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$d$ - Distance between plates.

Hence, the capacitance of the system is:

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$q = C\cdot V_{batt}$

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