S = 10 + (-4) = 6
Displacement is vector quantity
Answer:
Mirages happen when the ground is very hot and the air is cool.
Explanation:
They happen when light passes through two layers of air with different temperatures. The desert sun heats the sand, which in turn heats the air just above it. The hot air bends light rays and reflects the sky.
When you see it from a distance, the different air masses colliding with each other act as a mirror.
Answer:
u= 20.09 m/s
Explanation:
Given that
m = 0.02 kg
M= 2 kg
h= 0.2 m
Lets take initial speed of bullet = u m/s
The final speed of the system will be zero.
From energy conservation
1/2 m u²+ 0 = 0+ (m+M) g h
m u²=2 (m+M) g h
By putting the values
0.02 x u² = 2 (0.02+2) x 10 x 0.2 ( take g=10 m/s²)
u= 20.09 m/s
Answer:
141.14098 secs
Explanation:
Time taken to see the lightning flash can be gotten from:
Velocity = distance/time
Time = distance/velocity
Time = (47 * 1000)/(3 * 10^8)
Time = 0.0001567 secs
Time taken to hear the thunder can be gotten from:
Velocity = distance/time
Time = distance/velocity
Time = (47 * 1000)/(333)
Time = 141.14114 secs
The time lapse between the lightning flash and the thunder will be:
141.14114 - 0. 0001567
= 141.14098 secs