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 answer I'm pretty sure is 3
Answer:
(A) The correct answer is option (B) three halves that of the old unit.
(B) The answer is three fourth that of old unit
Explanation:
from the relation;
(A) Fromthe expression;
K = Qd/AΔT
Anew = 3/2 A(old)
(B)
K¹ = 2K(old), so we get
A(old) = A(old)/2
Combining with part A, we have;
Anew = 3/2 *A(old)/2
= 3/4A(old)
The answer is three fourth that of old unit
the answer is 1 because a single pulley has 1 rope
Answer:
the outer covering of a bird is usually for camoflauge (idk how to spell) or to attract mates and the outer part of a tree is used for protection i think, correct me if im wrong ;-;
Explanation: