Answer:
10.6 s
Explanation:
Given that a girl is running the 200 m dash. She starts by acceleration at 8m/s^2 for 7s. Then continues at this speed until the end of the race. How long did it take for her to complete the race?
Solution.
If she accelerated for 7s, the velocity at which she accelerated will be:
Acceleration = velocity/time
8 = V/7
Make V the subject of the formula by cross multiplying.
V = 8 × 7
V = 56 m/s
She maintains the speed through out the journey.
Speed = distance/time
Make time the subject of formula
Time = distance/speed
Time = 200 / 56
Time = 3.57s
Therefore, she will complete the race by 7 + 3.6 = 10.6 s
Answer:
Refraction is the slowing down of light waves as they pass into a different medium and speeding as they pass out.
hope it helps. plz mark me as brainliest.
Answer:
Explanation: RADIUS OF EARTH = 6400X1000m =
ACC DUE GRAVITY ABOVE SURFACE OF EARTH = g' =2.45 m/s^2
ACC DUE GRAVITY ON SURFACE OF EARTH =g= 9.8 m/s^2
A/C TO FORmULA
g'/g=1-2h/Re
g'/g +2h/Re = 1
2h/Re =1- g'/g
2h= (1- g'/g)Re
2h=(1-2.45 /9.8)
6400X1000
2h = (0.75)6400X1000
2h = 4800000
h= 2400000
m
