Answer:
v= s/t
Explanation:
250 km/ h =69.44m/s
S1=2 times 69.44 ≈ 139m
Next 2.5 seconds:
S2 = 100m
Average speed:
v=139m+100m/2s+2.5s = 239/4.5s = 53.2 m/s=192km/h
This is sort of simple. 2 grams of X can combine with 4 grams of Y to form XY. Y is 2 times the amount of grams in X. So if there are 11 grams of X there are 22 grams of Y to form XY. Or you could take 11 divided by 2 is 5.5 and then multiply 4 by 5.5 to get 22. If this is wrong please tell me I would be very happy to know.
Answer:
F= 25/2 = 12.5N
Explanation:
When you use a compound pulley the force required depends on the mechanical advantage of the compound pulley. This is known as rate of loss of distance or the ratio of the force to the load.
M.A = Effort distance /Load distance. OR M.A = Load/Effort
Answer:
The distance is
Explanation:
From the question we are told that
The initial speed of the electron is 
The mass of electron is 
Let
be the distance between the electron and the proton when the speed of the electron instantaneously equal to twice the initial value
Let
be the initial kinetic energy of the electron \
Let
be the kinetic energy of the electron at the distance
from the proton
Considering that energy is conserved,
The energy at the initial position of the electron = The energy at the final position of the electron
i.e

are the potential energy at the initial position of the electron and at distance d of the electron to the proton
Here 
So the equation becomes

Here
are the charge on the electron and the proton and their are the same since a charge on an electron is equal to charge on a proton
is electrostatic constant with value 
i.e
is the velocity at distance d from the proton = 2
So the equation becomes

![\frac{1}{2} mv_i^2 = 4 [\frac{1}{2}mv_i^2 ]- \frac{k(q)^2}{d}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%20mv_i%5E2%20%20%3D%204%20%5B%5Cfrac%7B1%7D%7B2%7Dmv_i%5E2%20%5D-%20%5Cfrac%7Bk%28q%29%5E2%7D%7Bd%7D)
![3[\frac{1}{2}mv_i^2 ] = \frac{k(q)^2}{d}](https://tex.z-dn.net/?f=3%5B%5Cfrac%7B1%7D%7B2%7Dmv_i%5E2%20%5D%20%3D%20%5Cfrac%7Bk%28q%29%5E2%7D%7Bd%7D)
Making d the subject of the formula



1. Mass number = Protons + Neutrons
Mass number = 26 + 32 = 58
2. Let the element be Xy
58Xy26
3. The proton number of Strontium is 38.
Mass = 38 + 50 = 88
4. 88Sr38
5. Let the atom be Ab
72Ab32