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ryzh [129]
3 years ago
7

Q 24, 25, 26 i dont get them and need answers for it

Physics
1 answer:
Alexandra [31]3 years ago
7 0

Answer:

24) W = 75 [J]; 25) W = 1794[J]; 26) n = 8.8 (times) or 9 (times)

Explanation:

24) This problem can be solved by means of the following equation.

DU = Q-W\\

where:

DU = internal energy difference [J]

Q = Heat transfer [J]

W = work [J]  

Since there are no temperature changes the internal energy change is equal to zero

DU = 0

therefore:

Q = W\\

The work is equal to the heat transfered, W = 75 [J].

25) The heat transfer can be calculated by means of the following equation.

Q = m*c_{p}*DT\\where:\\m = mass = 0.4[kg]\\c_{p} = specific heat = 897[J/kg*K]\\DT= 5 [C]

Q = 0.4*897*5 = 1794[J]

Work is equal to heat transfer, W = 1794[J]

26) Each time the bag falls the potential energy is transformed into heat energy, which is released into the environment. In this way the potential energy is equal to the developed heat.

E_{p}=Q\\\\E_{p}=m*g*h

where:

m = mass = 0.5[kg]

g = gravity = 9.81[m/s^2]

h = 1.5 [m]

E_{p}=0.5*9.81*1.5\\E_{p}=7.36[J]

The heat developed can be calculated by means of the following equation.

Q=m*c_{p}*DT\\Q=0.5*130*1\\Q=65[J]

The number of times will be calculated as follows

n = 65/7.36

n = 8.8 (times) or 9 (times)

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elena-14-01-66 [18.8K]

Answer:

The peak emf generated by the coil is 2.67 V

Explanation:

Given;

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time, t = 5 ms = 5 x 10⁻³ s

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V₀ = NABω

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V₀ = 940 x (π x 0.24²/4) x 5 x 10⁻⁵ x (2π/0.005)

V₀ = 940 x 0.04524 x  5 x 10⁻⁵ x 1256.8

V₀ = 2.6723 V = 2.67 V

The peak emf generated by the coil is 2.67 V

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Gravity on earth is 9.8 m/s squared, and gravity on the moon is 1.6 m/s squared. So if the mass of an object on earth is 40 kilo
garik1379 [7]

The mass of an object on Earth is the same as its mass on the Moon. The weight is different.

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3 years ago
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