Answer:
3.75 × 10⁻⁸ N
Explanation:
Given:
Intensity of the electromagnetic wave, I = 150 W/m²
Sides of the board = 25 cm (= 0.25 m) and 30 cm (= 0.30 m)
therefore,
the area of the rectangular box, A = 0.25 × 0.30 = 0.075 m²
Now,
force exerted on the card by the radiation, F = 
here,
C is the speed of the light = 3 × 10⁸ m/s
on substituting the respective values, we get
F = 
or
F = 3.75 × 10⁻⁸ N
Answer:
378 KWh
Explanation:
We'll begin by converting 1.2×10³ W to KW. This can be obtained as follow:
10³ W = 1 KW
Therefore,
1.2×10³ W = 1.2×10³ W × 1 KW / 10³ W
1.2×10³ W = 1.2 KW
Next, we shall convert 6.3×10² mins to hours (h). This can be obtained as follow:
60 mins = 1 h
Therefore,
6.3×10² mins = 6.3×10² mins × 1 h / 60 mins
6.3×10² mins = 10.5 h
Finally, we shall determine the electrical energy in KWh used for 1 month (i.e 30 days). This can be obtained as follow:
Power (P) = 1.2 KW
Time (t) for 1 month (30 days) = 10.5 h × 30
= 315 h
Energy (E) =?
E = Pt
E = 1.2 × 315
E = 378 KWh
Thus, the electrical energy used for 1 month (i.e 30 days) is 378 KWh.
Sensible heat involves change in temperature of a substance. As the name suggests, it is the heat one can feel or sensed. When a system exchange sensible heat, its volume, pressure and state do not change. The sensible heat can be measured with the help of thermometer. The other type of heat is latent heat which involves change in state of the substance.
Answer:
340 meters
Explanation:
For this we have to use the formula of constant velocity motion:
Because you hear the blows exactly 1 per second. And you hear only one blow after she finished, the sound takes one second to get to you.
