Answer:
option 4
Explanation:
Light's velocity in air ( 3 × 10^8 m/s ) is much greater than sound's velocity in air ( 343 m/s )
Hence due to difference in velocities , during lightning light is seen first & sound is heard later
the answer should be 20 seconds
Answer:
15 m per second
900m per minute
54,000 per hour
Explanation:
60 divided by 4 to get per second then times 60 for per minutes
then times 60 to get per hour
Explanation:
Spring is stretched by force f to distance
"X"
now here by force balance we can say
f = kx
k = !
now here we will we say that energy stored in the spring will convert into kinetic energy
kx² = mv²
(x² = mv²
now solving above equation we will have
PART 2)
now for half of the extension again we can use energy conservation
ka²-k(x/2)² = 1 {mv²
¾fx=mv²
now the speed is given as
3 fr 4m V=
