Answer:
3.73 * 10^16 photons/sec
Explanation:
power supply = 3.0 V
Emits 440 nm blue light
current in LED = 11 mA
efficiency of LED = 51%
<u>Calculate the number of photons per second the LED will emit </u>
first step : calculate the energy of the Photon
E = hc / λ
=( 6.62 * 10^-34 * 3 * 10^8 ) / 440 * 10^-9
= 0.0451 * 10^-17 J
Next :
Number of Photon =( power supply * efficiency * current ) / energy of photon
= ( 3 * 0.51 * 11 * 10^-3 ) / 0.0451 * 10^-17
= 3.73 * 10^16 photons/sec
Answer:
7327 kg or 7.3 tons
Explanation:
We have Newton formula for attraction force between 2 objects with mass and a distance between them:
where 
is the gravitational constant on Earth. 
is the masses of the 2 objects. and R = 2.6m is the distance between them.
is the attraction force.
or 7.3 tons
Question:
(a) She catches the Frisbee and holds it.
Answer:
The correct option is;
A perfectly inelastic collision
Explanation:
A perfectly inelastic collision is one in which there is maximum amount of loss of kinetic energy in the system. In a perfectly inelastic collision, the colliding members lose their initial speed and they stick together resulting in a loss of kinetic energy.
Since she catches and holds on to the Frisbee, the kinetic energy of the Frisbee is lost as she holds on to it so as to combine her mass to that of the Frisbee.
The temperature at which the sample of liquid turns to gas at 135 °C is termed as boiling point.
Answer: Option A
<u>Explanation:
</u>
The observation of conversion of liquid to gas indicates that there is occurrence of change in the state of matter. The inter-conversion from one state to another can be done by either varying the temperature or by varying the pressure.
In this case, the liquid on heating gets converted to gaseous state after attaining a particular temperature say 135 °C. So, this process of conversion from liquid to gaseous state on heating is termed as boiling.
The temperature at which a liquid converts to gas is termed as the boiling point of that liquid.
