I believe it’s OH have a good day
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
Here is your answer
b) 
REASON :
We know that
Velocity= Frequency× Wavelength
So,
Frequency= Velocity/wavelength
Here,
V= 3× 10^8 m/s
Wavelength= 2×10^-3 m
Hence,
Frequency= 3×10^8/2×10^-3
= 3/2 × 10^11
= 1.5× 10^11 Hz
HOPE IT IS USEFUL
Wave interference is the phenomenon that occurs when two waves meet while traveling along the same medium. The interference of waves causes the medium to take on a shape that results from the net effect of the two individualwaves upon the particles of the medium.Hope this help!
Answer:
To develop a molecular clock, you need to find which of the following?
a sequence of molecules
the rate at which changes occur in a type of molecule
how much total change has occurred in a type of molecule from two different species
how many molecules a species has
Explanation:
s;s;
