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3 years ago

How fast should a girl of 35 kg run so that her kinetic energy becomes 700J of?

Physics

2 answers:

Kipish [7]3 years ago

6 0

V^2 = 700J/0.5*35kg

V = square root of 40

v = 6.324 m/s

Alenkinab [10]3 years ago

6 0

Answer:

√40m/sec

Explanation:

As we know Kinetic energy = 1/2 mv^2

700 = 1/2 x 35 x v^2

1400/35 = v^2

√40 = v

So v, √40m/sec

Hope this helps you.

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Answer:

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=400Km/hr

=-400km/hr (because west direction)

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3 years ago

In the steady state 1.2 ✕ 1018 electrons per second enter bulb 1. There are 6.3 ✕ 1028 mobile electrons per cubic meter in tungs

bekas [8.4K]

Answer:

E=12.2V/m

Explanation:

To solve this problem we must address the concepts of drift velocity. A drift velocity is the average velocity attained by charged particles, such as electrons, in a material due to an electric field.

The equation is given by,

$V=\frac{I}{nAq}$

Where,

V= Drift Velocity

I= Flow of current

n= number of electrons

q = charge of electron

A = cross-section area.

For this problem we know that there is a rate of 1.8*10^{18} electrons per second, that is

$\frac{I}{q} = 1.2*10^{18}$

$A= 1.3*10^{-8}m^2$

$n=6.3*10^{28} e/m^3$

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We can find the drift velocity replacing,

$V = \frac{1.2*10^{18}}{(1.3*10^{-8})(6.3*10^{28})}$

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3 years ago

Bromine, a liquid at room temperature, has a boiling point

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3 years ago

A student standing on a stationary skateboard tosses a textbook with a mass of mb = 1.25 kg to a friend standing in front of him

juin [17]

Answer:

The velocity of the student has after throwing the book is 0.0345 m/s.

Explanation:

Given that,

Mass of book =1.25 kg

Combined mass = 112 kg

Velocity of book = 3.61 m/s

Angle = 31°