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2 years ago

A 70.0-kilogram man is walking at a speed if 2.0 m/s. What is the kinetic energy?

Physics

1 answer:

Paraphin [41]2 years ago

3 0

Answer:

140 J

Explanation:

From the the question, the mass of the man =70.0 kg and the speed at which the man is walking =2.0 m/s.

$K.E = \frac{1}{2}m {v}^{2}$

where K.E = the kinetic energy, m=mass and v= speed.

By substitution,

$K.E = \frac{1}{2} \times 70 \times {2}^{2}$

$\implies \: K.E = \frac{280}{2}$

$\implies K.E =140$

Hence the kinetic energy of the man is 140J

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2 years ago

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What is the maximum value of the magnetic field at a distance of 2.5 m from a light bulb that radiates 100 W of single-frequency

Anvisha [2.4K]

Answer:

$1.04\times 10^{-7}$ T

Explanation:

$IP$ = Power of the bulb = 100 W

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Intensity of the light at the location is given as

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2 years ago

A bottle lying on the windowsill falls off and takes 4.95 seconds to reach the ground. The distance from the windowsill to the g

Liula [17]

The distance an object falls from rest through gravity is
D = (1/2) (g) (t²)
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We want to see how the time will be affected
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So I'm going to start by rearranging the equation
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Multiply each side by 2 :         2 D =            g    t²

Divide each side by ' g ' :      2 D/g =                  t²

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Looking at the equation now, we can see what happens to ' t ' when only ' g ' changes:

-- ' g ' is in the denominator; so bigger 'g' ==> shorter 't'

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They don't change by the same factor, because 1/g is inside the square root. So 't' changes the same amount as √1/g does.

Gravity on the surface of the moon is roughly 1/6 the value of gravity on the surface of the Earth.

So we expect ' t ' to increase by √6 = 2.45 times.

It would take the same bottle (2.45 x 4.95) = 12.12 seconds to roll off the same window sill and fall 120 meters down to the surface of the Moon.

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2 years ago

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Answer:

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2 years ago

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77julia77 [94]

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