Answer:
D
Explanation:
A is wrong bc best DNA will survive
B is wrong because organism adapt not only for food source but to be able to live in the environment as well
C is wrong because single celled organisms don't adapt
The average speed is the ratio between the total space and the total time of the motion:
![v= \frac{S_{tot}}{t_{tot}}](https://tex.z-dn.net/?f=v%3D%20%5Cfrac%7BS_%7Btot%7D%7D%7Bt_%7Btot%7D%7D%20)
The total space is
![S_{tot}=63 km + 56 km = 119 km](https://tex.z-dn.net/?f=S_%7Btot%7D%3D63%20km%20%2B%2056%20km%20%3D%20119%20km%20)
while the total time is
![t_{tot}=2h+3h = 5h](https://tex.z-dn.net/?f=t_%7Btot%7D%3D2h%2B3h%20%3D%205h)
So, the average velocity is
![v= \frac{119 km}{5 h} =23.8 km/h ](https://tex.z-dn.net/?f=v%3D%20%5Cfrac%7B119%20km%7D%7B5%20h%7D%20%3D23.8%20km%2Fh%0A)
We can also rewrite it in m/s. The total space is
![S_{tot}=119000 m](https://tex.z-dn.net/?f=S_%7Btot%7D%3D119000%20m)
, while the time is
![t_{tot}=5h\cdot 3600 s/h = 18000s](https://tex.z-dn.net/?f=t_%7Btot%7D%3D5h%5Ccdot%203600%20s%2Fh%20%3D%2018000s)
, and so
Answer:
True
Explanation:
A convex mirror is a mirror whose outer bulging surface is the reflecting surface.
A convex mirror is used to see the distant objects and the image formed by the convex mirror is always erect and small. So, it is used as the rear view mirror.
It always forms a virtual, erect and diminished image of a real object.
It never forms a real image of a real object.
Answer:
Distance = 3.69 × 10^9 m
The distance from the probe to Earth is 3.69 × 10^9 m
Explanation:
Distance from the probe to the Earth can be derived using the simple motion formula;
Distance = speed × time .....1
Since a radio signal uses an electromagnetic wave to transfer signal, it has the same speed as the speed of light.
Speed of radio signal = speed of light = 3.0 × 10^8 m/s
time taken to reach the earth = 12.3 seconds
Substituting the values of speed and time into equation 1;
Distance = 3.0 × 10^8 m/s × 12.3 s
Distance = 36.9 × 10^8 m
Distance = 3.69 × 10^9 m
Note: all electromagnetic radiation have the same speed which is equal to 3.0 × 10^8 m/s
Answer:
v₁ = 1 [m/s].
Explanation:
This problem can be solved by using the principle of conservation of linear momentum. Where momentum is conserved before and after catching the snowball.
![P=m*v](https://tex.z-dn.net/?f=P%3Dm%2Av)
where:
P = linear momentum [kg*m/s]
m = mass [kg]
v = velocity [m/s]
![P=m*v\\P=5*10\\P=50[m/s]](https://tex.z-dn.net/?f=P%3Dm%2Av%5C%5CP%3D5%2A10%5C%5CP%3D50%5Bm%2Fs%5D)
As the momentum is conserved, it will be the same as that received by the person who catches the snowball.
![50= 50*v_{1}\\v_{1}=1[m/s]](https://tex.z-dn.net/?f=50%3D%2050%2Av_%7B1%7D%5C%5Cv_%7B1%7D%3D1%5Bm%2Fs%5D)
That is, the person who catches the snowball moves backwards with a speed of 1 [m/s].