Answer:
Colour of any object is by the colour of light it reflects i.e if white light is incident on the object,it will reflect blue color.so it will appear blue.But if red light is incident on it,it will not reflect that and absorb it.so as it will not reflect any light it will appear black.
Explanation:
E = mc²
E = 0.235 kg · (3×10⁸ m/s)² = 0.235 · 9×10¹⁶ kg·m/s²
E = 2.115×10¹⁶ J
The answer is d) 2.12×10¹⁶ J
Answer:
4
Explanation:
The reaction between hydrogen and oxygen gives water (H2O)
2H,+O, -> 2H2O
Oxygen is a gas O, = O2
Balancing both sides
let , be x
2x = 4
x= 2
Therefore, 2H2 = 4 hydrogen
Answer:
Width = 680 [m]
Explanation:
To solve this problem we must know the speed of sound in the air, conducting an internet search, we find that this speed has a value of v = 340 [m/s].
We apply the following kinematic equation, which relates space to time, to define speed.
v = x /t
where:
x = distance [m]
t = time [s]
v = velocity [m/s]
Now replacing:
x = 340 * 4
x = 1360 [m]
But the width of the cannon is calculated when the sound wave hits the wall of the canyon, so this width is half the distance.
Width = 1360 / 2 = 680 [m]
