The unit for measuring the rate at which light is radiated from a source is B, Lumen. Lumenous flux is the time rate of the flow of light, or the visible energy produced from a certain light source. It is the quantitative measure of brilliance of a light source. The unit we use for this is lumen.

8 0

2 years ago

Please answer of this question

Bogdan [553]

Answer:

$\frac{\pi }{15}$ m

Explanation:

At 10am, the minute hand and hour hand are ' 2 hours apart', since the minute hand is at 12pm and hour hand is at 10am.

Angle between the two hands = 2/12 * 360

= 60°

Arc Length = $2\pi r(\frac{60}{360} )$

= $2\pi (0.2)(\frac{1}{6} )\\= \frac{\pi }{15} m$

8 0

2 years ago

In a simple electric circuit, a 110-volt electric heater

Readme [11.4K]

Answer: 55 ohms

Explanation:

Given that,

Voltage of heater (v) = 110-volt

Current drawn by heater (I) = 2.0 amperes

resistance of the heater (r) = ?

Since voltage, current and resistance are involved, apply the formula for ohms law.

Voltage = current x resistance

i.e v = ir

where r = v / i

r = 110 volts / 2.0 A

r = 55 ohms

Thus, the resistance of the heater is 55 ohms

6 0

3 years ago