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Sphinxa [80]
3 years ago
11

A book falls off a desk. The book has a mass of 1.2 kg and was at a height of 0.9 m. How much mechanical energy does the book ha

ve just before it hits the ground? (Assume there is no air resistance.
Physics
2 answers:
Valentin [98]3 years ago
3 0
The book's potential energy will be converted entirely to kinetic energy at that point in the fall, since we can neglect losses due to air resistance. The potential energy is given by PE=mgh, where m=1.2kg, h=0.9m, and g=9.81m/s^2. This is the acceleration due to gravity.
This gives:
PE=1.2*0.9*9.81=10.59J
This is also the kinetic (mechanical) energy right before the landing.
EleoNora [17]3 years ago
3 0

Answer:

10.6 J

Explanation:

Apex

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From these examples, you can see a few things:

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An interference pattern is produced by light with a wavelength 580 nm from a distant source incident on two identical parallel s
irakobra [83]

Answer:

Explanation:

1 )

Here

wave length used that is λ = 580 nm

=580 x 10⁻⁹

distance between slit d = .46 mm

= .46 x 10⁻³

Angular position of first order interference maxima

= λ / d radian

= 580 x 10⁻⁹ / .46 x 10⁻³

= 0.126 x 10⁻² radian

2 )

Angular position of second order interference maxima

2 x  0.126 x 10⁻² radian

= 0.252 x 10⁻² radian

3 )

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I = I₀ cos²δ/2 ( δ is phase difference of two lights.

For angular position of θ1

δ = .126 x 10⁻² radian

I = I₀ cos².126x 10⁻²/2

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8 0
3 years ago
a ship travels a port p and travels 30 km due north. then it changes course and travels 20 km in a direction  30° east of north
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When we represent what is given to us on a coordinate plane, we have a figure as shown in the attachment.

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Component of D_{2} along X-axis is given by  D_{2x}  = D_{2} Sin 30 = 10 km

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