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allochka39001 [22]
3 years ago
10

A man drops a penny V=0 off the top of the Golden Gate Bridge how fast will the penny be moving when it hits the ground? The gol

den hat bridge is 275 meters tall
Physics
1 answer:
BARSIC [14]3 years ago
7 0

Answer:

Vf = 73.4 m/s

Explanation:

This is the case of vertical motion where we have to find the final velocity of the penny when it hits the ground. We can use 3rd equation of motion to find the final velocity:

2gh = Vf² - Vi²

where,

g = 9.8 m/s²

h = height = 275 m

Vf = Final Velocity = ?

Vi = Initial Velocity = 0 m/s

Therefore,

2(9.8 m/s²)(275 m) = Vf² - (0 m/s)²

Vf = √5390 m²/s²

<u>Vf = 73.4 m/s</u>

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Answer:

use the mole concept

Explanation:

the mole to mole ratio

4 0
3 years ago
Two circular coils are concentric and lie in the same plane. The inner coil contains 110 turns of wire, has a radius of 0.014 m,
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Answer:

The current flowing through the outer coils is  

Explanation:

From the question we are told that

   The number of turn of inner coil is N _i  =  110 \  turns

    The radius of inner coil is  r_i  =  0.014 \ m

     The current flowing through the inner coil is  I_i  =  9.0 \ A

     The number of turn of outer coil is N_o  =  160 \ turns

     The radius of outer  coil is r_o  =  0.022\ m

For net magnetic field at the common center of the two coils to be  zero  the current flowing in the outer coil must be opposite to current flowing inner coil

   The magnetic field due to inner coils  is mathematically represented as

            B_i  =   \frac{N_i \mu I}{2 r_i}

     The magnetic field due to inner coils  is mathematically represented as

            B_o  =  \frac{N_o \mu I_o}{2 r_o}

Now for magnetic field at center to be zero

             B_o  =  B_i

So

         \frac{N_i \mu I_i}{2 r_i} =  \frac{N_o \mu I_o}{2 r_o}

=>      \frac{110 * 9}{2 *  0.014} =  \frac{160 *I_o}{2 0.022}

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6 0
3 years ago
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Answer:

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8 0
3 years ago
A steady current I flows through a wire of radius a. The current density in the wire varies with r as J = kr, where k is a const
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B)

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8 0
4 years ago
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3 years ago
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