Answer: horizontal speed is 3.9 m/s
Explanation: when ball starts to drop, its vertical speed v0 is zero.
We can calculate dropping time from s = v0t +0.5gt².
Dropping time t= √(2s/g)= √((2·8.0 m)/9.81 m/s²)= 1.277 s
Because ball travels horizontal distance s= 5.0 m
HorizontalSpeed v = s/t = 5.0 m/1.277s= 3,915 m/s
Answer:
a) It is moving at 
when reaches the ground.
b) It is moving at 
when reaches the ground.
Explanation:
Work energy theorem states that the total work on a body is equal its change in kinetic energy, this is:
(1)
with W the total work, Ki the initial kinetic energy and Kf the final kinetic energy. Kinetic energy is defined as:
(2)
with m the mass and v the velocity.
Using (2) on (1):
(3)
In both cases the total work while the objects are in the air is the work gravity field does on them. Work is force times the displacement, so in our case is weight (w=mg) of the object times displacement (d):
(4)
Using (4) on (3):
(5)
That's the equation we're going to use on a) and b).
a) Because the branch started form rest initial velocity (vi) is equal zero, using this and solving (5) for final velocity:
b) In this case the final velocity of the boulder is instantly zero when it reaches its maximum height, another important thing to note is that in this case work is negative because weight is opposing boulder movement, so we should use -mgd:
Solving for initial velocity (when the boulder left the volcano):
The Law of Conservation of Energy states that, in an isolated system, energy remains constant and can not be created or destroyed, only transferred from one form to another. This law was created by Julius Robert Mayer.
Answer:
Energy = 1.38*10^13 J/mol
Explanation:
Total number of proton in F-19 = 9
Total number of neutron in F-19 = 10
Expected Mass of F-19
= 9*1.007 + 10*1.008 = 19.152 u
Actual mass of F-19 = 18.998 u
Energy of one particle of F-19 = 931.5*Δm = 931.5*(19.152-18.998)
= 143.234 MeV
Energy of one mole of F-19 = 143.234*10^6*1.6*10^-19*6.022*10^23
= 1.38*10^13 J/mol
1. New moon
This is because the moon comes between the Earth and sun and this is only possible during its new moon phase.
2. Full moon
This is because the Earth comes between the Moon and the sun and the effect is only visible when there is a full moon.
3. Corona
The corona is the outer layer and is the only one visible when there is an eclipse.
