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2 years ago

13

Hello....I need help with this question.

2 answers:

musickatia [10]2 years ago

6 0

Answer:

3.2 m/s²

Explanation:

Acceleration can be calculated as:

v = u + at (where v is final velocity, u is initial velocity, a is acceleration and t is time)

25 m/s = 9 m/s + a(5 s) (a is unknown)

16 m/s = a(5 s)

a = 3.2 m/s²

We assume that this is a uniform acceleration (meaning that the velocity increases at an equal rate for those 5 seconds).

erica [24]2 years ago

4 0

These are the steps to solving your question

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2 years ago

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61. A physics student has a single-occupancy dorm room. The student has a small refrigerator that runs with a current of 3.00 A

Mademuasel [1]

Answer:

Part a)

$percentage = 21.3$ %

Part b)

$percentage = 2.13 \times 10^{-5}$ %

Explanation:

As we know that total power used in the room is given as

$P = P_1 + P_2 + P_3 + P_4$

here we have

$P_1 = (110)(3) = 330 W$

$P_2 = 100 W$

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$P = 330 + 100 + 60 + 3$

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Part a)

Since power supply is at 110 Volt so the current obtained from this supply is given as

$110\times i = 493$

$i = 4.48 A$

now resistance of transmission line

$R = \frac{\rho L}{A}$

$R = \frac{(2.8 \times 10^{-8})(10\times 10^3)}{\pi(4.126\times 10^{-3})^2}$

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now power loss in line is given as

$P = i^2 R$

$P = (4.48)^2(5.23)$

$P = 105 W$

Now percentage loss is given as

$percentage = \frac{loss}{supply} \times 100$

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Part b)

now same power must have been supplied from the supply station at 110 kV, so we have

$110 \times 10^3 (i ) = 493$

$i = 4.48\times 10^{-3} A$

now power loss in line is given as

$P = i^2 R$

$P = (4.48 \times 10^{-3})^2(5.23)$

$P = 1.05 \times 10^{-4} W$

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$percentage = \frac{loss}{supply} \times 100$

$percentage = \frac{1.05 \times 10^{-4}}{493} \times 100$

$percentage = 2.13 \times 10^{-5}$ %

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2 years ago

A toy car on a string is pulled across a table horizontally. The string is at an angle

ddd [48]

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2 years ago

A trick shot archer shoots an arrow with a velocity of 30.0 m/s at an angle of 20.0 degrees with respect to the horizontal. An a

svlad2 [7]

Answer:

$u'=10.259\ m.s^{-1}$ is the initial velocity of tossing the apple.

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Explanation:

Given:

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$v'=u'-g.t'$

$0=10.259-9.8\times t'$

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$\Delta t=t-t'$

$\Delta t=1.0642-1.0469$

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