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3 years ago

PLEASE HELP

Physics

1 answer:

Anton [14]3 years ago

8 0

Explanation:

1st.

potential energy = 16 j

acceleration d t gravity = 9.8 m/s²

mass = 7 kg

we know

pe = m×g×h

16 = 7 × 9.8 × h

16 = 68.6h

16/68.6 = h

h = 2.16

2nd :

ke = 316 j

s = 10

we have

ke = 0.5×m×s²

316 = 0.5 × m × 10²

316 = 0.5 × m × 100

316 = 50m

316/50 = m

6.32 = m

m = 6.32 kg

may be check it once cuz I'm also not perfect at numericals too . I'm just 14 yo girl lol.

hope this helps :)

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where h is the Planck constant.

(b) By using the same procedure of part (a), we can convert the photon energy into Joules:
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The energy of a photon is related to its frequency f by:
$E=hf$
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$f= \frac{E}{h}= \frac{4.8 \cdot 10^{-19} J}{6.6 \cdot 10^{-34}Js} =7.27 \cdot 10^{14}Hz$

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Kinetic energy is a form of energy. It is defined as the energy associated with bodies that are in motion and this energy depends on the mass and speed of the body.

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Where Ec is kinetic energy, which is measured in Joules (J), m is mass measured in kilograms (kg), and v is velocity measured in meters over seconds (m / s).

In this case:

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Replacing:

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On the other hand, potential energy is the energy that measures the ability of a system to perform work based on its position. In other words, this is the energy that a body has at a certain height above the ground.

Gravitational potential energy is the energy associated with the gravitational force. This will depend on the relative height of an object to some reference point, the mass, and the force of gravity. Then for an object with mass m, at height h, the expression applied to the gravitational energy of the object is:

Ep = m*g*h

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<u><em>The total mechanical energy of the pizza crust is 19.2 J.</em></u>

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