A -..................................is the correct option
Answer:
By the use of slow motion camera.
Explanation:
Visually, it is very hard to differentiate between an ac and dc power supply. But Since, we that In Ac supply polarity changes 100 times in a second ( because frequency of ac supply is 50 Hz generally). Whereas, Dc gives a steady power supply. So, in slow motion camera we can easily capture the flickering light tubes which won't happen in case of dc supply.
Answer:
857.5 m
2.8583×10⁻⁶ seconds
Explanation:
Time taken by the sound of the thunder to reach the student = 2.5 s
Speed of sound in air is 343 m/s
Speed of light is 3×10⁸ m/s
Distance travelled by the sound = Time taken by the sound × Speed of sound in air
⇒Distance travelled by the sound = 2.5×343 = 857.5 m
⇒Distance travelled by the sound = 857.5 m
Time taken by light = Distance the light travelled / Speed of light

Time taken by light = 2.8583×10⁻⁶ seconds
Answer:
Startinfg speed is 13.82 m/s
Explanation:
Use equation for realtion between start and final speed :
Vf=Vs+a*t
Vf-final speed
Vs-start speed
Vf=24.44m/s
a=1.77m/s²(acceleration)
t=6.00s(Time)
Vf=Vs+a*t
Vs=a*t-Vf
Vs=1.77m/s²*6s-24.44m/s
Vs=-13.82m/s