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3 years ago

How efficient is an incandescent light bulb?

1 answer:

6 0

That depends on what you want to use them for.

As sources of light, they are somewhere around 15% - 20% efficient.

As heaters, they are somewhere around 80% - 85% efficient.

You might be interested in

If a runner has a speed of 8.66m/s and runs for 46.2s what distance is covered? tv = d

kati45 [8]

Answer:

$\text{Using the formula: }v=\frac{d}{t}\\\therefore vt=d\\\text{Plug and chug:}46.2(8.66)=400.092\text{ metres}$

6 0

2 years ago

Two resistors, R1=3.85 Ω and R2=6.47 Ω , are connected in series to a battery with an EMF of 24.0 V and negligible internal resi

Bond [772]

Answer:

(a) 2.33 A

(b) 15.075 V

Explanation:

From the question,

The total resistance (Rt) = R1+R2 = 3.85+6.47

R(t) = 10.32 ohms.

Applying ohm's law,

V = IR(t)..........equation 1

Where V = Emf of the battery, I = current flowing through the circuit, R(t) = combined resistance of both resistors.

Note: Since both resistors are connected in series, the current flowing through them is the same.

Therefore,

I = V/R(t)............. Equation 2

Given: V = 24 V, R(t) = 10.32 ohms

Substitute these values into equation 2

I = 24/10.32

I = 2.33 A.

Hence the current through R1 = 2.33 A.

V2 = IR2.............. Equation 3

V2 = 2.33(6.47)

V2 = 15.075 V

7 0

3 years ago

The rate at which energy is transferred is called

makvit [3.9K]

Answer:

The rate at which energy is transferred is called power and the amount of energy that is usefully transferred is called efficiency.

6 0

3 years ago

Read 2 more answers

How many newton-meters are equal to 1600 joules

Salsk061 [2.6K]

1 Joule IS 1 newton-meter.

7 0

3 years ago

A Chevrolet Corvette convertible can brake to a stop from a speed of 60.0 mi/h in a distance of 123 ft on a level roadway. What

Digiron [165]

Answer:

83.1946504051 m

Explanation:

u = Initial velocity = $60\ mph=\dfrac{60\times 1609.34}{3600}=26.82233\ m/s$

s = Displacement = $123\ ft=\dfrac{123}{3.281}=37.4885705578\ m$

$\theta$ = Angle = $26^{\circ}$

$v^2-u^2=2as\\\Rightarrow a=\dfrac{v^2-u^2}{2s}\\\Rightarrow a=\dfrac{0^2-26.82233^2}{2\times 37.4885705578}\\\Rightarrow a=-9.5954230306\ m/s^2$

Coefficient of friction

$\mu=-\dfrac{a}{g}\\\Rightarrow \mu=\dfrac{9.5954230306}{9.81}\\\Rightarrow \mu=0.978126710561$

$mg sin\theta - u mg cos\theta = ma\\\Rightarrow a=9.81(sin26-0.978126710561cos26)\\\Rightarrow a=-4.32382\ m/s^2$

$v^2-u^2=2as\\\Rightarrow s=\dfrac{v^2-u^2}{2a}\\\Rightarrow s=\dfrac{0^2-26.82233^2}{2\times -4.32382}\\\Rightarrow s=83.1946504051\ m$

The stopping distance is 83.1946504051 m

6 0

3 years ago