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3 years ago

What is the p.d. across a 4 resistor when there is a current of 0.3 A in it?

Physics

1 answer:

gregori [183]3 years ago

3 0

Answer:

1.2V

Explanation:

Given parameters:

Resistance = 4Ω

Current = 0.3A

Unknown:

Potential difference = ?

Solution:

To find the potential difference, we use the ohms law;

V = IR

Now, insert the parameters and solve;

V = 0.3 x 4 = 1.2V

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Explanation: hope this helps

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3 years ago

ns:Select the correct answer. In a video game, a flying coconut moves at a constant velocity of 20 meters/second. The coconut hi

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3 years ago

An object of irregular shape has a characteristic length of L = 0.5 m and is maintained at a uniform surface temperature of Ts =

goblinko [34]

Answer:

The value of the average convection coefficient is 20 W/Km².

Explanation:

Given that,

For first object,

Characteristic length = 0.5 m

Surface temperature = 400 K

Atmospheric temperature = 300 K

Velocity = 25 m/s

Air velocity = 5 m/s

Characteristic length of second object = 2.5 m

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$\dfrac{h_{1}L_{1}}{k_{1}}=\dfrac{h_{2}L_{2}}{k_{2}}$

Here, $k_{1}=k_{2}$

$h_{2}=h_{1}\times\dfrac{L_{1}}{L_{2}}$

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Put the value into the formula

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4 years ago

A certain car battery with a 12.0 V emf has an initial charge of 131 A · h. Assuming that the potential across the terminals sta

irga5000 [103]

Answer:

The battery can supply 130 W for 11.75 h

Explanation:

In order to discover the time in wich the battery can supply this energy we need to find how much current is being drawn from it, we do that by using the equation for real power that is P = V*I, since we have V and P we can solve for I as seen bellow:

I = P/V = 130/12 = 10.834 A

We can use this value to find how many hours the power can supply said current. We do that by dividing the current capacity of the battery by the current drawn:

t = 141/12 = 11.75 h

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3 years ago

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3 years ago