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2 years ago

If a 60 W light bulb and a 75 W light bulb operate from 150 V source, which bulb has a greater current in it?

Physics

1 answer:

Monica [59]2 years ago

8 0

Answer:

Since it us the resistance that causes the power output, it might be intuitive to think that more resistance produces more power but as P=I^2 * R one actually needs high current and low resistqnce. That means 75 W has lower resistance and higher current.

Now you may think that making the resistance very low, one gets the most power. Not so, as the circuit has wires, power source etc. All the have their resistance. In theory one gets the maximum power over a resistor when the resistor is half of the total resistance of the circuit. This in practice would be inefficient as one would lose half of the total power elsewhere. In practice circuits have fuses that limit the current and one gets the maximum power at the current the fuse is rated to. So if there is 20 A fuse, the maximum power is 2400 W and the corresponding resistance 6 ohm.

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Flint glass materials

Kipish [7]

Answer:

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Explanation:

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3 years ago

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Two coconuts fall freely from rest at the same time, one from a tree twice as high as the other. If the coconut from the shorter

valentinak56 [21]

Wee can use here kinematics

as we know that

$y = v*t + \frac{1}{2} at^2$

for shorter tree we know that

$y = 0 + \frac{1}{2}*9.8 * 2^2$

$y = 19.6 meter$

now since we know that other tree is twice high

So height of other tree is y = 39.2 m

now again by above equation

$y = v*t + \frac{1}{2} at^2$

$39.2 = 0 + \frac{1}{2}*9.8 * t^2$

$t = 2.83 s$

so the time taken is 2.83 s

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3 years ago

Can someone help me?

Leviafan [203]

Car X traveled 3d distance in t time. Car Y traveled 2d distance in t time. Therefore, the speed of car X, is 3d/t, the speed of car Y, is 2d/t. Since speed is the distance taken in a given time.

In figure-2, they are at the same place, we are asked to find car Y's position when car X is at line-A. We can calculate the time car X needs to travel to there. Let's say that car X reaches line-A in t' time.

$V_x .t' = 3d\\ \frac{3d}{t} .t' = 3d\\ t'=t$

Okay, it takes t time for car X to reach line-A. Let's see how far does car Y goes.

$V_y.t = \frac{2d}{t} .t = 2d$

We found that car Y travels 2d distance. So, when car X reaches line-A, car Y is just a d distance behind car X.

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2 years ago

You are a visitor aboard the New International Space Station, which is in a circular orbit around the Earth with an orbital spee

Alchen [17]

Answer:

The minimum total speed is 11.2km/s

Explanation:

We are been asked to find the escape velocity.

Escape velocity is defined as the minimum initial velocity that will take a body(projectile)away above the surface of a planet(earth) when it's projected vertically upwards.

The formula to calculate the escape velocity is Ve = √2gR

For the earth g = 9.8m/s2 , R = 6.4*10^6

Substituting into the equation Ve = √2*9.8*6.4*10^6 = 11.2*10^3m/s

=11.2km/s

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Aneli [31]

Both of the above! :)

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